Causticum Anhang 4
Siehe Causticum Anhaengsel
[Karl-Heinz Jansen and Dirk Thomas Quak]
First published in AHZ 4 2018; 263: 1–15, translated by Chris Kurz, with
permission of the Georg Thieme Verlag KG Stuttgart. New York
Summary
The homeopathic materia medica of Causticum described by Hahnemann is,
due to the mixing of the symptoms of “Tinctura acris sine kali” with those of
the Causticum distillate later described in chronic diseases, still uncertain
today. However, the substances produced by Hahnemann’s Causticum syntheses are
also not clearly defined chemically. We therefore repeated Hahnemann’s
production procedure of Causticum several times in a modern research laboratory
under various conditions and analyzed
the distillations with elaborate chemical investigations, the results of
which bring essential and new aspects into discussion.
Method of Preparation of “Causticum” by Samuel Hahnemann
“Take a piece of freshly burned
lime of about two pounds, dip this piece into a vessel of distilled water for
one minute, then lay it in a dry dish, in which it will soon turn into powder
with the development of much heat and its peculiar odor, called lime – vapor.
Of this fine powder take two ounces and mix with it in a (warmed) porcelain
triturating bowl a solution of two ounces of bisulphate of potash, which has
been heated to red heat and melted, cooled again and then pulverized and
dissolved in two ounces of boiling hot water. This thickish mixture is put into
a small glass retort, to which the helm is attached with wet bladder; into the
tube of the helm is inserted the receiver, half submerged in water; the retort
is warmed by the gradual approach of a charcoal fire below and all the fluid is
then distilled over by applying the suitable heat. The distilled fluid will be
about an ounce and a half of watery clearness, containing in concentrated from
the substance mentioned above, i. e., Causticum; it smells like the lye of
caustic potash. On the back part of the tongue the caustic tastes very
astringent and in the throat burning; it freezes only in a lower degree of cold
than water, and it hastens the putrefaction of animal substances immersed in
it. When Muriate of Baryta is added, the Causticum shows no sign of sulphuric
acid, and on adding oxalate of ammonia it shows no traces of lime.”
Background
Pierre Schmidt and Jost Künzli von Fimmelsberg recommended purportedly a
local application of Causticumin liquid form in simple cases of burns. Our idea
to develop a lotion, gel or spray with Causticum for external application
required us to manufacture our own Causticum to satisfy the requirements of a
sterile manufacturing chain.
After an exhaustive study of the literature we were puzzled by the
question: what actually is Causticum. A question previous experimental
researchers have been puzzled by as well.
Excursion into the Chemistry of Hahnemann’s period
The “caustic principle” as Hahnemann understood it.
In manufacturing Causticum, Hahnemann, like many other chemists and
alchemists of his time, was motivated by the search for the “caustic principle”
of alkaline and basic substances
“… the caustic lye salts …, which now forms their composition, gives
them also the corrosive property and deserves the name aceture or causticum.”
(Hahnemann S: Aetzstoff and Hydras Caustici, Journal for chemistry and physics,
in connection with several scholars, LVI volume, hall at Eduard Anton 1829).
There existed the idea that the effect of alkaline substances on living
organisms (corrosive, burning, irritating, biting, tanning, dissolving, etc.)
is caused by a specific caustic substance, waiting to be discovered.
“What is the caustic principle found in living lime and corrosive
alkalis is not yet clear; but that it does exist, and that it does not depend
on an alkaline base, becomes clear on account of the strong medicinal effects
of the (tincture-saturated) tincture of caustics “(from: Hahnemann:” Fragmenta
“, note to Acris Tinctura, 1824).
Composed Matter
Hahnemann held the opinion that one never encountered absolutely pure
substances in chemistry. He considered all matter “composed” and therefore of
complex composition. Understandably, he thought that a yet unknown substance
had to be responsible for the “caustic action”:
“All material perceptible by our senses, as simple as it appears, is
always composed, just as every decomposition is conditioned by a new, different
composition. Thus the caustic lye salts are not uncomposed substances, just as
the freshly calcined (and extinguished) lime is simply lime earth. “(From
Hahnemann: Journal for Chemistry and Physics 1829: Aetzstoff and Hydras
Caustici).
Accordingly, composed matter was considered in Hahnemann’s times to
consist of individual particles. “Binding agents and active principle” were
also held to be material particles. There was, of course, no notion of charged
atomic nuclei and electrons to explain the principle of chemical bonds. The
molecular structure of water was also still unknown.
Principles of Modern Acid-Base Chemistry
According to Brønsted and Lowry, we today define a base as a substance
capable of accepting H+– ions, i.e., a proton acceptor. In aqueous solutions,
the proton acceptor
is the hydroxyl ion, OH-. The corresponding cation is called the H+-ion.
At the time of Hahnemann, the principles of acid-base chemistry were
still unknown. The hydroxyl ion OH- as proton acceptor (base) and the hydronium
ion H3O+ as proton donor (acid) were only postulated in 1887 (44 years after
Hahnemann’s death) by Svanthe Arrhenius and incorporated into a complete model
in 1923 by Johannes Nikolaus Brønsted.
Modern chemistry explains atomic bonds and electrons involved therein through
their difference electronegativity, i.e., the varying capability of atoms to
attract electrons in
a chemical bond. The dipole moment of water, with its negative charge
distribution around the oxygen atom and the resulting positive net-charge around
both hydrogen atoms is the mediator of the “caustic property”when a base is
added. A OH– -ion is formed by protolysis (the “caustic principle” of alkaline
substances).
Acids and basis in the “old school” chemistry
At Hahnemann’s time, the term “alkaline basis”, denoted the alkaline
reaction of substances, which formed bases by dissolving in water. Alchemy, the
predecessor of chemistry, knew several forms of lye as bases:
Limestone: calcium
carbonate(CaCO3),
burnt lime, quicklime: calcium
oxide (CaO)
slaked lime: calcium
hydroxide(Ca(OH)2),
but also natron (NaHCO3), sodium carbonate (Na2CO3), potash (K2CO3) and
ammoniac (NH3).
The chemical composition of these compounds lay still in the dark and
chemical formulas like the ones quoted above were also unknown. The periodic
table of elements would only be discovered in 1869.
“… burnt lime (has) … added another substance to its composition, which,
unknown to chemistry, gives it its corrosive nature, and its solubility in
water to lime water.
This substance, although not acid itself, gives it the caustic power …
“(from Hahnemann:” The chronic diseases: Causticum”, 1828).
The term “basic” (in the meaning of alkaline) was hardly used at the
beginning of the 19th century. Rather, one talked of substances with
caustic properties. In English, potassium hydroxide is still today called
“caustic potash”. This property as ascribed to the “fire element” (derived from
ancient Greek καυστόςmeaning “burnt”),
because this corresponded to the haptic and sensory experience associated with
these substances. Chemistry back then was largely experienced, felt, smelled
and tasted than understood
by abstract formulas like today.
The considerable amount of heat released (exothermic reaction) when
calcium oxide is slaked with water, forming calcium hydroxide, was interpreted
as part of the caustic principle, similar to the corrosive and burning
properties on the skin and mucus membranes. These were imagined to be some kind
of “fiery agent”, because fire has the quintessential property of “burning”.
Manufacturing of Bases in the 18th century
Through a reaction of burnt lime (calcium oxide) with dissolved soda
(sodium bicarbonate) or potash (potassium carbonate) one knew already how to
produce the “caustics”, caustic of sodium (NaOH) and caustic of potassium
(KOH). This “caustification” (to render caustic, corrosive) of soda and potash
was essential to the manufacture of soap. These procedures were common
knowledge and already used semi-industrially. From his writings, e.g., Apotherlexikon
of 1793, one can infer that Hahnemann was an experienced chemist, experimenter
and physician, who was up-to-date on the knowledge of his time.
Transference of the “caustic principle” onto water
“Causticum sine Kali” meant to Hahnemann “caustic principle separated
from potassium”, which he imagined as a separable, material substance he called
Causticum:
“I would like to know how such a strange substance, promising as it is
for the Arztey art, which gives it the corrosive property as constituent element
of the etching bases, and in this composition has such a great affinity for the
oxygen, that it quickly becomes with it transformed into chalkegas, which makes
the bases (to a certain extent neutralized and) mild, while separating the
atmospheric air from the etching bases by adding a completely moist acid to the
bases and then by distillation, in combination with water, as hydras caustici I
am interested in, I say, how one can still refuse this essential substance of
citizenship in the realm of chemistry “(from Hahnemann: Journal of Chemistry
and Physics 1829: Aetzstoff and Hydras Caustici).
We therefore interpret Hahnemann’s manufacturing procedure of Causticum
as the attempt to chemically separate the postulated (and as he writes himself)
“hitherto unknown by chemistry” caustic (basic) principle (by today’s standards
the properties of the hydroxyl ion OH–) from burnt and slaked lime (i.e.,
calcium hydroxide, Ca(OH)2) and transfer it onto water by distillation.
Saturation of Bases to liberate Causticum
The article published in Journal für Chemie und Physik, 1829, and cited
above shows clearly Hahnemann’s intention to transfer the caustic principle to
water by distillation. He defends is hypothesis about Causticum:
“When the caustic bases are saturated by a liquid acid, the caustic
substance is transferred onto the water in the mixture and yields a Hydras
caustici. Distilling this compound of caustic base with the acid – provided the
acid is not in excess – over a sand bed until all water has evaporated, drives
this new composite (Hydras caustici), by all appearances as pure water, over to
the other side. Was the amount of water initially small, and hence the
aggregate of the caustic principle with water concentrated, its taste on the
tongue will at first be cool, then astringent and finally burning on the palate,
similar to Mezereum…”
It was Hahnemann’s intention to isolate the caustic principle as
material substance from a “liquid acid” (a solution of potassium sulfate)
saturated by a “base” (slaked lime)
by distillation. This is the reason which led him to the circuitous
process of synthesizing a solution of caustic potash (KOH) as a step to his
distillation of Causticum, even though he was familiar with the usual
preparation of caustic potash from burnt lime (CaO) and potash (K2CO3).
The Idea of “Hydras Causticum”
Hahnemann’s idea of a “Hydras Causticum” (caustically reacting water),
in which water is the carrier medium of the caustic property, is not far removed
from the mechanism of protolysis in water.
Particularly considering how clearly Hahnemann already spoke to the
reaction of carbon dioxide with water (published in Journal fürChemie und
Physik, 1829). He was able to explain the reaction of carbonic acid with
calcium hydroxide (slaked lime) only via “Hydras Causticum”, because gaseous
carbon dioxide (i.e., CO2, which, however, in water forms H3O+ + HCO3 ) does
not react with calcium hydroxide, as he was able to demonstrate in meticulous
experiments.
“Perhaps only, or at least most frequently, the caustic principle is
contained in three compounds,
with bases (alkaline salts,
Fuller’s earth etc.);
with carbon (in glowing coals,
extinguished under mercury) (Note by the authors: Hahnemann perhaps refers to
the writing of Joseph Priestly (1733- 1804), the first to discover oxygen (“air
freed of phlogiston”) and
with water.
Only in the first two cases can Causticum by contact with atmospheric
air (the oxygen contained therein) be converted to acids, (Note of the authors:
It is not oxygen but CO2which reacts in connection with water. Maybe Hahnemann
thought that carbon, in connection with Causticum and oxygen, yields carbonic
acid, in the sense of: carbon (C) + oxygen (O2) will not react to H2CO3 but
2OH– + CO2 = H2CO3)) which we will, by tradition, call chalk-acid, while
recently they have been termed carbon-acid. Thus the bases become bland and the
coal turns to chalk-acidic gas (carbon dioxide).”
At this point Hahnemann goes on to describe the chemical properties of
CO2 and not, as he assumes, of Causticum and oxygen. If one mixes “air” (which
contains CO2) with water, CO2 is dissolved under dissociation (HCO3 ). Is the
solution saturated with calcium hydroxide (slaked lime), chalk precipitates
(chalk milk; it is converted to calcium carbonate and hence “bland”).
He calls carbonic acid “chalk-acidic gas”, because of its emergence
during burning of lime and because pure carbonic acid can only be produced
under very specific circumstances outside of an aqueous solution. It does,
under normal conditions, not exist in liquid form.
In his explanations Hahnemann follows the thoughts of the Frenchman
Antonine de Lavoisier (1743- 1794) who discovered that solutions of certain
oxides (e.g., sulfur dioxide) react acidic. This proved to Lavoisier that all
acids had to contain oxygen. A belief that was only disproved by Justus von
Liebig (1803-1874) who showed in his Elementar analyse (1831) that there,
indeed, exist acids which do not contain oxygen. But Liebig, just as Hahnemann,
failed to develop a general model for bases.
The “caustic principle” (Causticum) is Hahnemann’s model for the
transformation of slaked lime to chalk-water by introduction of air into the
aqueous solution.
For him, the decisive factor is oxygen, who reacts with the “chalk-acid
gas” (carbonic acid). He considers Causticum to be the catalyst of this
reaction.
Isolation of the caustic principle by distillation
Furthermore, he is convinced that the caustic principle can be isolated
by distillation, if he saturates the “bases” (slaked lime) with a “wet acid”
(solution of potassium sulfate), so that the caustic principle is released.
This is the point at which Hahnemann went wrong, we realize today. Steam
distillation does not transfer either acid components (cations) nor alkaline
components (anions) to the other phase, since they remain as salts in the
distillation flask. Using chemically pure substances, the distillate contains
only water (H2O) with its own temperature dependent auto-protolysis. Such a
distillate is, ideally,pH-neutral and contains no contaminations. Hahnemann
writes:
“Every (acid), even chalk-acid (carbonic acid), separates Causticum from
the corrosive bases, in the presence of water with which Causticum combines to
Hydras caustici.”
In his understanding, the principle of base-acid chemistry lies in the
transference of the alkaline properties of a substance by way a “substance”,
which exists only in connection with water. This is, in principle, correct, except
one cannot separate the OH–ion from KOH as the alkaline properties (i.e., the
pH) is determined by the modified behavior of valence electrons of molecules in
solution. In other words, the alkaline properties are determined by the extent
of protolysis (relative abundance of H3O+-ions to OH–-ions)
in an aqueous solution.
According to Hahnemann, the “material” property being transferred is
corrosiveness. The more of the caustic principle is contained in a substance,
the more corrosive it is.
This is analogous to the idea of a “heat principle”, which he mentions
sometimes. The “heat principle” is, in his interpretation, a substance added to
a compound by heating, and which is released again by burning. At his times
this theory (Phlogiston theory) was wide spread and capable of explaining
oxidation and reduction processes. It yielded, for the first time, a framework
to classify certain groups of substances which form acids and bases. It was
also the starting point for the investigation of the physics of gases.
Until the beginning of the 20thcentury, it was a commonly held belief
that qualitative properties of matter are conveyed by specific carrier
substances. The concept of “ether” as a carrier of electromagnetic waves was
only finally disproved by quantum physics and Einstein’s theory of relativity.
Modern physics has expanded this idea and now speaks of “gauge particles” as
mediators of forces, e.g. photons, gravitons and gluons as the quanta for the
electromagnetic, gravitational and strong nuclear force, respectively.
Hahnemann’s Causticum hence describes the „relationship“ between acids
and bases. It is the substance of common inter-est (inter-est: from Latin
inter-esse, that which is in between): they both are “corrosive”
“Entirely and absolutely simple substance are not detected by our
senses: no man has ever seen such…This caustic principle in isolation and by
itself is likewise undetectable, just as undetectable as are the simple
substrates of gases (oxygen, nitrogen, and so forth) to our senses…That, which
is part of their composition, also lends them their corrosive property and
deserves to be called caustic principle or Causticum.”
The substance carrying the corrosive property is, to Hahnemann,
Causticum.
Experimental Setup and Procedure
Prior to the determination of the experimental setup it was expected
that, according to current know-how, the procedure described by Hahnemann can
only result in pure water in the condensed distillate. Therefore, considerable
attention was put on historic conditions (impurities, apparatus, handling),
which determined the experimental setup at Hahnemann’s time.
According to Hahnemann’s original instructions, 50 g (2 oz.) each of
slaked lime Ca(OH)2 and potassium sulfate, K2SO4, were homogenized with 50 ml
of boiling water in a porcelain mortar. This suspension (“magma”) was heated in
a distilling flask to dryness. The escaping vapor was condensed in a cooler and
collected in fractions. The entire experiment lasted about 90 minutes,
resulting in individual distilled fractions of ca. 10 ml.
Three different apparatus were used for the experiment:
500 ml Duran flask with ground
glass seal (Schott); Claisen distillation bridge with 40 cm Liebig cooler (Lenz
Laborglas); 20 ml Duran culture vials (Schott) with screw top for collection of
individual fractions.
500 ml Duran flask with ground
glass seal (Schott); 1000 ml alchemic still (alembic) of Duran glass with bent
run-off (Neubert glass); 20 ml Duran culture vials (Schott) with screw top for
collection of individual fractions.
1000 ml historic flask of
green lime-natron-glass with matching historic alembic; historic glass vials
(ca. 30 ml) for collection of individual fractions.
Controlled heating, in order to test the effect of temperature, was
accomplished on one hand by an oil bath and a laboratory-grade heating stirrer
(Bibby Sterlin) up to 200° C.
nd on the other hand (comparable to a classic sand bed over an open
flame) over an electronically controlled heating mantle (Witeg Heating Mantle)
up to 420° C.
Fig. 1: Different experimental setups, from modern to historic; (a)
modern distillery; (b) schematic design of modern distillery, (c) drying of
air-filled pig bladders; (d) pig-bladder seal on historic flask;
(e) experimental setup with flask and alembic from Hahnemann’s period.
Temperature was recorded over the entire duration of the distillation by
Pt100 temperature sensors and, additionally, by contactless infrared
thermometer.
According to setup and research goal, different temperature profiles and
different final temperatures between 200 and 400° C were employed.
The following parameters were measured in the individual distilled
fractions:
Cation-chromatography
(detection threshold [DT] ca. 10 μg/l) for Li, Na, K, NH4, Mg, Ca and
Anion-chromatography (DT ca.
10 μg/l) for F–, Cl–, NO2–, Br–, NO3-, PO43-, SO42- and organic
Amino-acid analysis (DT ca. 10
pM) for the 40 most commonamino-acids.
pH-value via apH-sonde.
Photometry (DT ca. 20 μg/l)
for silicates.
Determination of silicates was
only carried out once in some trials (due to the volume required for the test)
using 1 ml of each of the final three fractions. In later trials, with already
higher concentrations of silicates detected in the mixed fractions, 1 ml was
taken from each individual fraction, diluted 1:5 with water, and tested
individually for silicates, without mixing.
For the individual trials, chemicals were used from different sources
and preparations: For calcium hydroxide we used the following preparations:
Calcium hydroxide, chemically
pure (GPR RECTAPUR®VWR)
Calcium oxide (VWR),
chemically pure, slaked with demineralized water (Sartorius, IP Arium Comfort)
Certified marble, chemically
pure calcium carbonate (Merck), burnt 4 h at 1100° C in tantalum oxide
crucibles, slaked with demineralized water.
Isar-chalk, calcium carbonate,
burnt 4 h at 800° C in corundum crucibles, slaked with demineralized water
Isar-chalk, calcium carbonate,
burnt 4 h at 1100° C in corundum crucible, slaked with demineralized water
For potassium sulfate we used the following preparations:
Potassium sulfate, chemically
pure, (GPR RECTAPUR®VWR)
Potassium hydrogen-sulfate
(Alpha Aesar), melted and roasted over open flame (ca. 1100° C) in a porcelain
crucible.
For water we used the following sources.
Tap water from
Fürstenfeldbruck
Demineralized water from a
mixed-bed preparation with activated charcoal filter and UV irradiation.
Conductance less than 0,1 μS (Sartorius, IP AriumComfort)
During particular trials, 0.5 g of crushed chalk-natron glass was added
to simulate the quality of glass used at the time of Hahnemann.
In reproductions of historic setups used in Hahnemann’s period, original
(ca. 1830) glass apparatus was used, which was sealed with dried pig bladders,
cut in stripes and
re-moistened (as described in the literature of the period). This kind
of sealant was also used for several trials in conjunction with modern
equipment for simulation purposes.
Each setup was tested by distilling 50 ml of pure water in order to
determine the base values for the particular materials used.
Since the particular usage history of the historic apparatus was unknown
they were carefully cleaned mechanically and rinsed for several days with
demineralized water.
The affluent water was examined and found to be unremarkable in all
analyzed parameters.
The Chemistry of the Reaction
In his manufacturing instructions for Causticum, Hahnemann uses slaked
lime (calcium hydroxide) in conjunction with molten potassium hydrogen-sulfate
(potassium sulfate) with the addition of water in a classical exothermic
reaction to yield potassium hydroxide (in solution solution) and calcium
sulfate (gypsum). This aqueous suspension (termed “Magma” by Hahnemann) was
then distilled.
By melting of potassium hydrogen sulfate Hahnemann synthesizes potassium
sulfate under evaporation of SO3:
2KHSO4 T —-> K2S2O7+H2O T —-> K2SO4 + SO3
He then goes on to mix pulverized potassium sulfate with slaked lime and
hot water:
K2SO4 + Ca(OH)2+Aqua —->
2 KOH (potassium hydroxide) + CaSO4(gypsum)+ Aqua
Afterwards, he distills the reaction mixture to dryness.
Ratio of Molar Masses
Two ounces (ca 50 g) of each of the reactants are mixed:
50 g potassium sulfate (K2SO4: M =174,3g/mol) =>287mmol 50 g calcium hydroxide
(Ca(OH)2: M =74,1g/mol) =>676mmol 50 g Aqua (H2O: M =18g/mol) => 2780mmol
Assuming complete stoichiometric reaction of potassium sulfate in KOH,
we arrive at the following stoichiometric yields:
287 mmol K2SO4 + 670 mmol Ca(OH)2
+ 2780 mmol H2O
574 mmol KOH + 287 mmol CaSO4 * 2 H2O + 383 mmol Ca(OH)2 + 2206 mmol H2O
—->
Checking the input quantities against the yield of the reaction
products:
574 mmol KOH: (KOH: M = 56,1 g/mol) =>32,3 g
287 mmol CaSO4 *2 H2O (CaSO4
*2 H2O: M = 172,1 g/mol) =>49,4
g
383 mmol Ca(OH)2 (Ca(OH)2
: M = 74,1 g/mol) =>28,4 g
2206 mmol H2O (H2O: M =
18 g/mol) =>39,8 g
As expected, this yields a mol-mass of 3450 mM (1244 mM without water)
and
a total weight of149.9 g (discrepancy due to rounding errors).
Stoichiometric
ratios of ions in the reaction product:
KOH (574 / 1244) = 46%
Ca(OH)2
(383 / 1244) = 31%
CaSO4*2H2O
(287 / 1244) = 23%
If bumping during boiling (boiling delay) should happen, then the
“splashes” ought to contain the individual ions in the calculated
stoichiometric ratio.
Calcium hydroxide as “Causticum”: the bumping hypothesis of Grimm
In the article “Causticum: Caustic Principle or Phantasy?”, published
1989, Grimm presumes delayed boiling with ensuing bumping during the
distillation process.
This has become a widely accepted hypothesis today, even though it is
known that Hahnemann was familiar with the problem of bumping during
distillation.
He describes in detail how to avoid it in his Apothekerlexikon. He
recommends using a thermometer and knows about controlled heating using a sand
bed.
Furthermore, Hahnemann checks his distillate using specific
precipitating reactions to exclude impurities due to bumping or other causes.
He wants to ensure that his Causticum is not contaminated by sulfuric acid or
calcium hydroxide. He manages to do this, employing state-of-the- art methods
of his time.
Exclusion of KOH-Concentrations above 1% by Hahnemann’s Oral Test
Hahnemann starts by describing a test based on taste:
“…tastes astringent at the back of the tongue and extremely burning in
the throat…”
Should, as Grimm describes [2], a bumping during delayed boiling have
led to concentrations above 1% of KOH, this would have resulted in cauterized
and necrotized tissue in the oral cavity. The oral test, as described by
Hahnemann, excludes the possibility of this having happened.
If Transference by Bumping then Transference of All Minerals
Then Hahnemann checks his distillate for impurities using two
precipitating reactions:
“…upon addition of salt-acidic barite (barium chloride), no trace of
sulfuric acid; and upon addition of oxalic-ammonium(ammonium oxalate), no trace
of chalk detectable.”
Grimm’s hypothesis of bumping during boiling (transference of KOH to the
distillate) explains the important “corrosive” properties of Causticum, but not
the absence of sulfate and calcium.
If one supposes bumping, like Grimm does, as an inadvertent mechanism of
transferring minerals or salts, one should be able to detect all other
minerals, e.g., calcium sulfate, in their respective abundances, next to KOH.
This, however, Hahnemann disproves using the precipitating reaction with
ammonium oxalate:
Ca2+ (aq) + (NH4)2C2O4 →
CaC2O4 (white precipitation) + 2 NH4+ (aq)
Hahnemann’s demonstration of absence of sulfur also excludes transference
of gaseous SO2 or SO3 dissolved in the vapor to the distillate.
Hahnemann uses the precipitation of insoluble barium sulfate with barium
chloride to demonstrate the absence of sulfate ions.
SO42- (aq) + Ba2+ → BaSO4
Possibility of Transference by Bumping Only within the Solubility
Product of Barium Sulfate and Calcium Oxalate. Since both Hahnemann’s tests,
for sulfate as well as for calcium, were negative, one can safely assume that
no bumping during delayed onset of boiling happened.
From our point of view, only transference in minute amounts within the
solubility product of barium sulfate and calcium oxalate are conceivable,
because those would not
have been detectable by Hahnemann. What does this mean for possible
concentrations of KOH in the distillate?
SolubilityBaSO4: 2,2 mg·l-1 (18°
C)
SolubilityCaC2O4: 6,1
mg·l-1 (20° C)
Of BaSO4 (M=233.4 g/mol) there are, hence, only 9.4 µmol/l soluble.
Rounding up to 10 µmol/l this results in a maximum possible ion concentration
in the distillate:
10 µmol/l CaSO4*2H2O: → 400 µg/l Ca + 960 µg/lSO4
13,5µmol/lCa(OH)2 → 539 µg/l Ca + 459 µg/lOH
20µmol/lKOH
→ 780 µg/l K + 340
µg/lOH
If there had been bumping during the distillation process (in the form
of minute splashes), then Hahnemann’s detection method excludes concentrations
in excess of 1mg/l for all involved ions (anions as well as cations).
This means that Hahnemann’s detection reaction by precipitation of
barium sulfate (solubility product 2.2 mg/l) with ammonium oxalate is capable
to exclude involuntary transference of the order of the 150-th part of a single
droplet.
Concentration of at most 799 µg/l of free OH–-ions can arise. This
modifies the calculated pH of water to that of a very weak base (pH 9.67). In
vivo this theoretical value
is never reached, because the small number of OH–ions are buffered
immediately by the reaction equilibrium between liquid and external air.
Furthermore, not all OH–ions
are completely dissociated.
Skin or mucus membranes neutralize bases having a pH up to 11.5 quickly
by CO2-diffusion. Only at a pH above 11.5 does necrosis and hence corrosive
damage of the skin arise. Bases typically taste bitter and soapy in higher concentrations.
Purportedly the detection level of KOH by taste lies between 1 and 50 mg/l .
Potassium hydroxide in solution, which would be present due to bumping
during boiling within its solubility product, would have a maximum
concentration of 0.799 mg/l. This cannot be detected by taste, would not lead
to corrosive damage of the skin and would not explain the properties as regards
taste (“…tastes astringent at the back of
the tongue and extremely burning in the throat..”) of his Causticum.
Sublimation of KOH at High Temperatures
Another common explanation for the emergence of a dilute solution of
potassium hydroxide is the dry evaporation of KOH in the flask at very high
temperatures. The melting point of pure potassium hydroxide, which heralds the
beginning of sublimation (evaporation), is 360° C (the boiling point of KOH is
1327° C). Temperatures of 300-400° C
are reached, if at all, only toward the end of distillation, after all
water has evaporated from the flask. This, however, defines the end of the
distillation process, according to Hahnemann. He would have had to expose the
flask to high temperatures over a longer period (without apparent result to
him) at the end of the process (when the “last” drop has already been
transferred), in order for the temperature to reach 360° C in the interior of
the flask.
Alembics and glass flasks were very difficult to get and very expensive
at the time of Hahnemann. They were made of temperature sensitive chalk-natron
glass. It seems unlikely that Hahnemann, who was demonstrably carful,
meticulous and following the highest standards, would have exposed them
unnecessarily to high temperature variations over a longer period and risk
shattering them in the process.
Even if one assumes that temperatures in excess of 360° C were reached
in the distillation flask, a transference of KOH by sublimation to the liquid
fraction is still impossible. Without a phase of water vapor or liquid
condensate of water (which both are absent at this point in time) gaseous KOH
would have to reach the other side of the cooler. However, as soon as the
temperature drops below the sublimation temperature of 360° C, KOH solidifies
and is not carried further. In the alembic’s beak the required 360° C are never
reached and decline, at the end of the process, to far below 100° C. In our
experiments we extended the heating period several minutes at a temperature of
400° C measured at the flask. No rise in potassium concentration was
discernible.
We deem it impossible that relevant amounts of KOH could be transferred
to the distillate using Hahnemann’s procedure, without transference of other
reactants for the following reasons:
Fractioned analysis of the
distillate for cations and anions by ion-chromatography.
Measurements of conductance.
Accurately documented
temperature profile during distillation.
Measurement of pH.
Careful and repeated
observation of the process.
Above mentioned reasoning.
Under the given conditions it is implausible that KOH should have
reached the distillate by sublimation.
Formation of Ammonia during distillation
Numerous replications and interpretations of the historic experimental
setup of Hahnemann confirmed the presence of ammonia in the distillate. Since
ammonia reacts alkaline in water, this could be a possible candidate for
Hahnemann’s Causticum.
We can identify two possible sources of ammoniac on our experiments:
Ammonia from ammonia salts
contained in feldspar and biotite-minerals present in chalk in various amounts.
Ammonia from alkaline
hydrolysis of the pig bladders used as seals between flask and alembic.
In our analyses, Ammonia was, in fact, detectable even without using
pig-bladder seals. The explanation is the presence of feldspar and
biotite-minerals, present in chalk as impurities, which contain ammonia. The
melting point of these minerals is far beyond 1100° C and could, therefore,
survive the burning process of chalk. However, ammonia in our analysis is only
detectable in minute quantities and only by high-pressure-liquid-chromatography
(HPLC). This ammonia is formed only during the last fraction and at high
temperatures in the alembic, when the last drop of water evaporates (“distilled
up to dryness”). With respect to the entire amount of distillate of ca. 50 ml,
Hahnemann would not have been able to detect these trace amounts of ammonia.
During distillation, ammonia cannot neither be detected by smell, nor made
visible by acetate proof, nor by litmus (pH).
Using pig bladder seals on the alembic, significant amounts of ammonia
are formed across all fractions (with the highest concentration in the last
fraction). They are clearly detectable by olfaction as well as by a litmus
test, as they move the pH far into the alkaline region.
Hahnemann Was Familiar with the Chemistry of Ammonia
Ammonia (NH3) is a colorless gas, readily soluble in water. It has a
particularly pungent smell and is very poisonous. However, because of its very
strong, typical and unpleasant odor the danger of accidental poisoning is very
small. The threshold for olfactory detection of ammonia gas in humans falls
between 0.018 and 70.5 ppm.
The deadly dose by inhalation is LCLo=10000 ppm within 3 hours, and
hence is a factor 103 to 105 higher than the olfactory threshold.
Ammonia was discovered 1776 by Johann Kunckel. Carl Wilhelm Scheele
demonstrated 1773 the existence of oxygen and nitrogen and recognized nitrogen
and hydrogen
as the composing agents of ammonia. This was also known to Hahnemann.
Scheele published his results 1777 in his only book “Chemische Abhandlungen von
der Luft und dem Feuer”, which Hahnemann probably cites in his Apothekerlexikon
under Ammonia. In addition, Hahnemann herein describes his experience with
Ammonia during the production of Causticum:
“Alkaline Salt of Ammonia: (sal alkali volatile). The so-called volatile
alkaline salt, the composition of which has been plausibly explained by recent
authors as being of phlogistic (Remark of authors: nitrogen) and flammable
(Remark of authors: hydrogen) air by way of the heat principle. This origin
demonstrates also, why it can be found in all three kingdoms of nature, even
though we draw the most of it from animal substances. Its particularly
volatile, pungent odor, especially in conjunction with caustics and Causticum,
distinguishes it easily from other substances.”
Hahnemann was familiar with the smell and chemistry of ammonia:
“In combination with other acids to form neutral salts, it does not have
this odor. However, upon grinding the neutral salt (e.g., salt of salmiac) with
burnt lime it is released promptly and escapes, the alkaline salt combined with
the caustic principle of lime, perceptible by its well-known odor which bites
in the nose.”
He also was well versed in the usual methods of detection of his time:
“Should there be too little of it present, or is its odor masked by
other smells for it to be identified, one must only hold an open vial of acetic
acid next to it. A white fog (Remark of authors: ammonium acetate) will form
above it, if free ammonia was indeed present
… The nature of other compounds with alkaline salt of ammonia teaches us
the art of separation…”
It is, therefore, safe to assume that Hahnemann recognized the ammonium
odor during his distillation, which forms naturally in distillations of all
bases in conjunction with the use of sealants composed of animal matter. We can
also assume that he will have attempted to minimize this effect, particularly
since he was a decidedly practical, experienced and well versed chemist.
Ammonia from the sealant material of the alembic
Using the distillation procedure of Hahnemann, an alembic is fixed to
the flask. There exist various methods of sealing the alembic to the flask.
With today’s distilling apparatus featuring ground glass connectors, one would
wrap pig bladder seals around the plug and thereby place the sealant material
between plug and glass.
With a historic alembic, however, the sealant (strips of pig bladder) is
wrapped around the shaft of the flask and finally the alembic fitted onto it.
Thereby the sealant is placed on the outside of the flask without direct
contact to the substrate within. It will, however, make contact with the hot
condensate of the distillate at the edge of the gap.
Hahnemann’s distillation apparatus
The sealant in Hahnemann’s distillation apparatus comprised of pig
bladder, which was dried and cut in strips. These dried strips were moistened
before use and wrapped around the flask. Then the alembic was put on top and
“glued” to the flask. The “moist bladder” formed a gluey strip around the shaft
which exuded gelatin and fat, thereby rendering it impermeable to air and
vapor.
The pig bladder is heated within the sealant gap by heat conduction of
the glass. Exuded fat starts to boil and splash along with the condensate in
the form of micro-drops into the alembic. Additionally, the mixture of fat and
protein creeps along the glass surface across the inner surface of the
apparatus. Proteins (amino acids) contained in the pig bladder thereby make
their way into the vessel. The “steamed” exudate drips in small quantities from
the retort back into the flask. By alkaline hydrolysis of the amino acids,
small quantities of ammonium (and also low amines) are formed, which are
readily detectable by their smell.
Fig 3: Alembic and positioning of pig bladder seal. Drawing of distill
taken from Apotherkerlexikon by Hahnemann.
Some more modern alembics, which were available already at the time of
Hahnemann, were made of glass and copper. They featured a cylindrical extension
at the bottom
of the retort, which could be inserted into the flask. Using this rather
rare apparatus, the sealant covers the inside of the flask’s sealing surface.
The exudate of the pig bladder can then drip directly back into the flask and
hence leads to the formation of considerable quantities of ammonia through
alkaline hydrolysis.
Consequently, the amount of ammonia produced varies with the
localization of the sealant material. It is, however, at sufficient
temperature, unavoidable. Hahnemann has detailed knowledge of the properties of
ammonia and understands also the way it is formed at the contact of a solution
of potassium hydroxide with animal matter.
Still, he insists that his Causticum is a unique substance. Why?
Formation of Hydrated Silicates during Distillation
Hahnemann expects to isolate the substance responsible for the alkaline
reaction, Causticum (today one would say the hydroxyl-ion), by distillation. In
the distillate he finds
a substance which he cannot detect directly chemically (as opposed to
ammonia), whose taste and odor he can identify, and which is clearly different
from ammonia.
This substance (his “caustic principle”) constitutes not potassium
hydroxide, as chemists later claim, but a by-product of his apparatus, which was
largely unknown to the chemistry of his period.
Fig 4: Formation of ammonia from the sealant material and of hydrated
silicates from the glass flask in conjunction with hot potassium hydroxide
solution. Ammonium silicates are hence formed in the gaseous phase. During
heating of a potassium hydroxide solution in a flask made of chalk-natron
glass, silicates are formed, which are released from the glass surface during
distillation! This is clearly visible as
a milky opacity and a roughening of the interior surface in flasks which have
been used repeatedly to “cook” alkaline solutions. Because crystalline and
liquid potassium hydroxide corrode glass under formation of water soluble
silicates, these substances are today only stored in plastic bottles.
Modern distills (like we are using) consist of inert Duran glass, from
which nearly no SiO4 molecules (silicic acid) are released. In order to
simulate the chalk-natron glass in Hahnemann’s flask, we added a small amount
of crunched chalk-natron glass to Hahnemann’s Magma. The effect is surprisingly
clearly detectable in the distillate. The surface nanostructure of silica gel
(about 500-1000 m2/g) is perfectly suited for absorbing moisture from air or
for drying solid substances. This explains the astringent sensation on the
tongue and in the throat upon tasting by Hahnemann.
Hydrated silicates are volatile in water vapor. Investigations of the
thermodynamics of mono- and di- silicates [17] show that they are present in
water vapor (which explains their presence in our setup) and that they have the
property to condense to silicate compounds (e.g., in the presence of aluminum
and zeolites).
There existed no procedure to detect silicates directly at the time of
Hahnemann. The specific chemistry of hydrated silicates appears to be very
complex and was entirely unknown back then. So these silicates remained
undiscovered and were understandably interpreted incorrectly by Hahnemann. In
fact, he had synthesized a new substance, wholly unknown to chemistry of his
time, which is until today used successfully as a homeopathic remedy.
Potassium silicates exhibit an alkaline reaction in water, under
formation of OH-:
K4SiO4+H2O —-> 4 K+ +
3 OH– +H3SiO4–
On one hand, the positively charged cation, potassium, is formed but
next to it also another cation, H3SIO4 , which is relative to OH positively
charged (less electronegative). In this manner a “caustic substance”
(dissociated silicic acid) emerges, according to Hahnemann’s imagination.
Hydrated silicates can, under certain circumstances, condense to larger,
cyclic or cage-like structures (also known as “soluble glass”) which lend it a
viscous consistency. Sodium silicate (or potassium silicate) was then and now
produced by melting a mixture of quartz and soda (or potash) at temperatures of
1200-1500° C. Or, still unknown
at Hahnemann’s time, by chemical pulpation of quartz with sodium
hydroxide (or potassium hydroxide) in the autoclave at 200° C. Soluble glasses
harden to so-called silica gels upon exposure to air, mostly due to a reaction
of alkali meta-silicate with carbon dioxide or carbonic acid, according to this
reaction formula:
K2SiO3 + H2CO3
—–> K2CO3 + H2SiO3 (Gel
SiO2 • nH2O)
Direct acidification of soluble glass yields first silicic acid which
proceeds to polymerize spontaneously to silica-gel. Silica-gel is a gelatinous
mass and comprises of spherically shaped poly silicic acids connected by oxygen
bridges, and whose interstitial spaces are filled with water. When this watery
gel is dried at higher temperatures, a hard silica gel is formed
(“Xerogel”). The surface nanostructure
of silica gel (about 500-1000 m2/g) is perfectly suited for absorbing moisture
from air or for drying solid substances.
This explains the astringent sensation on the tongue and in the throat
upon tasting by Hahnemann.
Hydrated Silicas and Ammonia: pH-dependent Formation of
Ammonia-Silicates
Ammonia forms in water an equally remarkable alkaline solution. It
dissociates in water under release of energy to hydroxyl and ammonium ions.
NH3+H2O —–> NH4+ + OH– +Heat
Upon heating and evaporation of the water, ammonia will again completely
transition into the gas phase. Silicates are water soluble as silicic acids,
which, however, depends strongly on pH and temperature. At a pH of 7 and 25° C,
solubility is at about 100 mg/l. At pH>12 and 100° C it rises to ca. 1000
mg/l. Silicic acid transitions into the vapor phase, which, by the way, poses a
permanent problem for the industrial generation of steam.
We assume the following mechanisms, happening in parallel, during
Hahnemann’s distillation:
Formation of silicic acid at
high pH and transition into the vapor phase. —-> SiO2 + 2 H2O
Si(OH)4
Formation of gaseous ammonia
through alkaline hydrolysis of the pig bladder eluent and dissociation in the
distillate.
NH3
+ H2O <===>
NH4OH
Formation of soluble ammonia
silicate
2NH4OH + Si(OH)4
——-> (NH4)2SiO3 + 3
H2O
Silicic acid would condense by deprotonation into chains of poly-silicic
acid of various length, which would be detectable by a cloudiness of the
solution. An excess of ammonia, however, leads to a disproportionation of the
silicic acid and forms soluble ammonia silicate. In water, ammonia-ions and
hydrated silicates form monomeric semi-stable ammonia silicates of the formula
(NH4)2SiO3 (ammonia-meta-silicate). Ammonia hampers polymerization of silicates
and, in this way, stabilizes the silicate solution. After some time, through
acidification, cooling or heating, the ammonia silicates can again decompose.
Ammonia escapes as a gas and silicic acid is formed, which, in turn, goes on to
polymerize to gelatinous meta-silicates.
Experimental Results
Using salts of different origins
yielded nothing significantly different from ordinary water in the Duran glass
apparatus. Taste test according to Hahnemann was negative.
Using pig bladder as sealant
or adding it to the mixture in the flask resulted in formation of ammonia.
The historic apparatus made of chalk-natron
glass and using pig bladder as sealant yielded ammonia and silicate in the
distillate. The taste was as described byHahnemann.
The particular temperature
profile used during distillation had a significant effect on the yield of
ammonia.
The abundance of ammonia
increases steadily over the fractions. Concentrations of silica reach a maximum
beyond which they do notincrease.
A trial using classical
conditions and the historic apparatus led to crystallization in the first
fraction 24 hours after cooling. Following fractions remained clear. Testing
for silicate after dissolving the crystals in alkali waspositive.
Gentle heating (oil bath)
resulted in significantly smaller concentrations of ammonia and silicate. Only
trials using self-burnt lime, high temperatures, the addition of chalk-natron
glass (or using historic glass vessels) and the use of pig bladder as sealant
material showed robust analysis results of individual constituents in the
distillate (Fig.s 5, 6, 7,8)
Our Causticum distillation experiment with crushed chalk-natron glass
resulted in clearly detectable concentrations of 5-6 ml/l in the distilling
receiver. A trial with historic chalk-natron glass flask and alembic (both
dating from the period of Hahnemann) gave concentrations between 3-4 mg/l even
without addition of crushed chalk-natron glass. Distillates are clearly
identifiable by taste: the taste like silica gel and leave a strong, lasting
feeling of desiccation in mouth and throat. The solution is clear and has a pH
of 9.7.
Fig. 7: Individual fractions of distillation F1-F5, evolution of
silicate, ammonia and pH.
Fig 8: Cation profile of individual fractions (F1-F5 and pure water
distillation) of the distillation experiment using original vessels and pig
bladder seals (V16) by HPLC-analysis.
Ammonia silicates exhibit properties which match the chemical and
physical properties described by Hahnemann for his Causticumto a surprising
degree:
Completely soluble in water.
Can be distilled at ca. 100° C
or are carried over by water vapor.
Clear and colorless
insolution.
Smell similar to potassium
hydroxide.
Oral sensation of binding
water (“tastes astringent at the back of the tongue and extremely burning in
the throat”).
Lowers the freezing point
(ammonia meta-silicates are used as anti-freezeagents).
Hastens putrefaction (through
denaturation ofproteins)
No precipitation with barium
(“upon addition of salt-acidic barite, no trace ofsulfuric acid…can be discerned”)
No reaction with ammonia
oxalate (“and upon addition of oxalate of ammonia, no traceof chalk”): absence
of calcium = no white precipitate of calcium oxalate.
According to our hypothesis, Hahnemann synthesized alkaline, water vapor
voluble, ammonia silicates in aqueous solution instead of the universal caustic
principle (Causticum), a certain “caustic” substance from the mixture of
potassium hydroxide, calcium sulfate, pig bladder seal and the chalk- natron
glass of the distillation flask.
He was the first physician and chemist to make them available as
homeopathic remedy. Further trials will
provide us the opportunity to optimize the composition of Causticum
quantitatively and qualitatively further.
Acknowledgements
Our research on Causticum was funded by the Sanddorf-Foundation
Regensburg.
We thank Dr. Kathrin Bretthauser for the exhaustive editing of our text,
the glass collectors Birgit and Dieter Schaich for the distills of the period
of Hahnemann, Mrs. Claudia Rühle of the Museum of Medical History Ingolstadt,
Mrs. Anne Roestel of the German Museum of Apothecary Heidelberg, Mrs. Marianne
Hasenmayer of the Glass Museum Spiegelberg, Dr. Susanne Rehn-Taube of the
German Museum in Munich and Mrs. BeateSchleh of the Library of the Institute of
Medical History of the Robert Bosch Foundation for their helpful informations,
Dr. Julie Christoffel of Brahms Pharmacy in Regensburg for the production of
Causticum spray and Causticum potencies according to our manufacturing protocol,
Mr. Wolfgang Courth of the Leonardo Pharmacy in Hamburg for providing low
potencies of Causticum for analysis, Mrs. Christina Grundler for the
possibility to burn lime, the butcher shop Boneberger in Fürstenfeldbruckfür
numerous pig bladders, Prof. Sylvia Schnell of the University Gießen for
numerous laboratory glasses.
Editors Note: The authors would like to discuss their results about the
correct way of producing Causticum and its
influence on the homoeopathic pharmacopoeia, with a producer of homeopathic
remedies, a pharmacy. If you would like to get in touch with the authors
regarding the same, please post a message in the comment box below.
cancerCancer Is Not a Disease in Itself but the Outcome of Some Kind of
Internal Disturbance
Homoeopathic Management of PneumoniaHomoeopathic Management of Pneumonia
You may also like
History of Homeopathy – Part III
A brief account of Dr. Richard Haehl's 23 year long quest for
Hahnemann's documents.
Autopathic Detoxication – Part II
Part 2 of Jiri Cehovsky's article on the use of potentized saliva in
healing. Numerous cured cases...
Garuda Biodynamic Research Institute (NZ)
The Garuda Biodynamic Institute, (GBI) is based in Te Puke, New Zealand.
It is focused on...
About the author
Karl Heinz Jansen
Born 1953, studied general chemistry and nuclear procedural techniques
at the School for Applied Sciences Aachen, dept. Jülich, business
administration and controller academy (Sunnyvale). Product specialist Dionex
International, Department Head environmental analytics Biotronik, Product
Manager SYKAM GmbH, CEO Scintronics GmbH. Currently managing director SYKAM
Chromatography. 40 years of professional experience in chromatography, trace
analytics, quality control and admittance tests in pharmacology,
development of synthesizers for radio pharmacology and QP for amino acid
analytics, co-founder of Sykam GmbH, IBJ, LCA Laboratory for chromatographic
analysis, Scintomics and Sykam Chromatography. Founder of the research company
jaqu-invent (2017), together with Thomas Quak.
View all posts
About the author
Dirk Thomas Quak
Dirk Thomas Quak, MD
Born 1967, studied medicine and graduation at LMU München. Founding and
head of the student circle homeopathy on the medical faculty of LMU between 1989
and 2009. Three years full-time assistant with Dr. Michael Barthel. Teacher:
Jost Künzli, Horst Barthel, Dario Spinedi. Private practice since 1997.
2002-2009 co-manager of HTPZ in Munich. 2009 foundation of Homeopathic Academy
for Postgraduate Education in Fürstenfeldbruck. Board member of the Hahnemann
Society 2008- 2011. Research delegate of ECH and project group master studies
of the DZVhÄ 2007-2010. Since 2016 head of student circles Homeopathy at the
University of
Regensburg and Witten-Herdecke. Book publications: “Clarkes Praktische
Materia Medica” and “Leitfaden Homöopathie”, co-author of “Adjuvante
Homöopathie in der Onkologie”. Founded the research company jaqu-invent 2017
together with Karl Heinz Jansen.
---------------------------------------
Literature
Block B: Das Kalkbrennen, 2. Auflage, Leipzig, Verlag Otto Spamer, 1924.
Grimm A: Causticum: Ätzstoff oder Phantasieprodukt?, KH 33(1989), Seite 47-57. Hahnemann S: Die Chronischen Krankheiten, 5 Bände, Dresden, Leipzig: Arnold, 1828–1830. Hahnemann S: Fragmenta de viribus medicamentorum positivis sive in sano corpore humano observatis. Pars prima. Textus. Leipzig: Barth, 1805.
Hahnemann S: Apothekerlexikon Samuel Hahnemanns, der Arzneigelahrtheit Doktors und Mitglied einiger Gesellschaften, Leipzig: Crusius; 1798.
Hahnemann S: Aetzstoff und Hydras Caustici, Journal für Chemie und Physik, in Verbindung mit mehreren Gelehrten, LVI. Band, Halle: bei Eduard Anton, 1829.
Holzapfel K: Causticum Hahnemanni – welches Causticum? ZKH 2012; 56 (1): 18–28. Stüttgen G: Funktionelle Dermatologie, Springer, 1974.
Kopp, H: „Die Geschichte der Alkalien“, gelehrte Anzeigen, Jan-Jun 1846, München: Verlag der königlichen Akademie der Wissenschaften, S. 1011-1015.
McKee J. E. and Wolf H. W.: 1963 Water Quality Guidelines. Second
Edition, Pub. No. 3-A. Resources Agency of Calif., State Water Resources
Control Board.
Schott Technische Gläser, Physikalische und chemische Eigenschaften,
1999.
Schmid R: The Structure of Trisodium Hydrogensilicate Dihydrate:
High-Temperature, Acta Cryst. (1981). B37, 789-792.
Tamahrajah J: Experimental and theory-based studies of silicic acid
formation under hydrothermal conditions – evaluation of various methods,
Dissertation 2015, Universität Oldenburg.
Weiss A: Kationenaustausch und innerkristallines
Quellungsvermögen bei den Mineralen der Glimmergruppe, Z. Naturforschg. 11 b, 435-138, 1956.
2 Comments
Martin Earl
February 10, 2019 at 7:25 pm
Congratulations to Karl Heinz
Jansen and Dirk Thomas Quak for undertaking this complex task. If we want
predictable results, we must know about the substances our remedies are made
from. Causticum has always held a mystery.
Reply
Kris
August 11, 2020 at 11:54 pm
Hi. Does anybody knows any pharmacy
that makes that kind of Causticum?
Reply