or the O- side). Carbon is the pole which lies diametrically opposite to the fixed, stabile elements of the noble gas series (likewise the steadiers of the balance), when one considers the periodic system pictorially as a spiral arrangement on a cylinder surface. The longer the arms of the “balance” through the deposit of new elements on both sides, the more living the play of the balance or to leave the illustration: there develops from the point of departure C that unending series of new configurations, from whence (materially considered!) finally the living from is born, bloms, or whatever word may be used to symbolically designate it since a mechanistic expression is unsuitable. This place of a new addition in the natural structures also signifies for our consideration, the material reciprocal actions with the living man, a new exit and at the same time a crossing. The carbon compounds which we include withe bridge, from the plant and animal medicinal substances.
From group IV only the first two elements carbon, carbonicum, C, and Silicium, Si, are drawn into the circle of our consideration. These two tetravalent amphoteric elements appear in nature as powerful opponents; carbon as the point of departure and pillar of the entire organic world, silicium as the inorganic crust of the solid earth shell down to a depth of 1100 km. If carbon once appears in the oxygen compound CO2 in the circulation of life then it unfolds the infinitely great number of carbon compounds, beyond human comprehension, by virtue of carbon having the capacity of self-combination in series and rings and through the innumerable and easily convertible compounds particularly with H and O. In contrast to the unlimited alterations in shape, the oxygen compound of silicium, SiO2, stands as a rigid inorganic principle.
Thus at first glance the cleft between these two neighbors seems unbridgeable. If however one draws carbon into comparison only in so far as appears in the life of the organism or after its return from the circulation of life into an elementary from, then obviously the chemically inert “coal” (if we employ this embracing name here apart from the various physical structures and the almost constant admixture of other substances) then it is on an even plane with silicium. Both are almost chemically inert. Both come into consideration for reciprocal action with the organism by forces of the same type, surface powers which become effective through physical subdivision, the collodial state. Physical structure differentiates the actions of these charge carrying molecular aggregates more than does the nuclear charge differences of the elements formed.
On this account the medicinal relationship of silicic acid to carbon comes much more distinctly in evidence, the nearer the latter approaches the pure elementary and t the same time mostly inorganic form. Among the common medicinal substances graphites fulfill these presumptions the nearest. Therefore we shall open the carbon series with it after we have first learned silicium in the oxygen compound as a drug.
Silicium in the form of silic acid salts next to oxygen is the most extensive element of the lithosphere, and it is fundamentally the chief constituent of the earth crust. Bunge gives a picture of the struggle of carbonic acid with silicic acid for predominance in the building of the earth crust. Silicium appears as silicates in the plant and animal organisms. It will concern us only in this form or as the anhydride of silicic acid, silicium dioixide, SiO2.
The colloidal nature of pure silicic acid seems to have been known to Paracelsus because he states in the Book “De natura rerum”: “the life of quartz and flint stones is a mucilaginous material”.
APPEARANCE AND SIGNIFICANCE IN PLANTS AND ANIMALS
The content in silicic acid seems to decrease in the series of organisms from the lower plants to the higher animals. In the plants it appears as a supportive substance. It is abundant in alga, equisetum, polygonum, and grasses; in bamboo it is enriched in the so-called sections in the region of the nodes. Even today it plays a great role as a drug in the Orient.
Herbivorus animals are also richly supplied with silicic acid. In sheep and swine formation of silicate stones may occur. Also in animals silicic acid always passes into the supportive substance, it forms the shells in some, and in birds the ashes of the feathers have an especially high content. In man silicic acid appears most strongly in the connective tissues, in the skin and its appendages, nails and hair. The regular total content in the human body however is small, about 0.001 Percent.
That silicic acid appears in the urine (average 0.1 gram per day) suggests an actual silicate metabolism. Moreover it is also excreted through the large bowel after absorption. In the excretion from the large intestine of a man whose natural feces were passed through an artificial fistula in the small intestine the ash amounted to 3.15 Percent determined as SiO2. The loss of SiO2 with skin desquamation, nails and hair, makes some additions necessary.
Even in plants the role of silicic acid is probably not exhausted with the supportive function. As a hydrophile colloid silicic acid can retain water in varying amounts, indeed amounting to multiples of its own weight. It may be remembered that the plants growing on stony soils are able to create a considerable water reserve through this property of silicic acid. The increased absorption from a siliate rich soil also proves a defense against drying.
In the human organism apparently the function of silicic acid is supporting and structure giving, because it is found most abundantly in the particularly resistant tissues. Thus silicic acid in the organism forms a counterpole to the supportive function of calcium which prevails in part in the carbonic acid, the close neighbour of silicic acid.
Silicic anhydride, SiO2 is chemically very inert, being attacked only by the fluoride ion. The essential silicate functions are physical in type. SiO2 is a colloid of complicated structure, is highly molecular, is difficult to break down, and also physically difficult to attack. It is never in true solution but only colloidally dispersed. Actual salts of silicic acid occur only in solid form, and they are peculiarly complex compounds of the metal oxide with SiO2; for example Na2SiO3 is decomposed in water to NaOH and SiO2.
SiO2 is a negative colloid, as most body colloids which however arise from carbon. With this may be associated the extensive independence of silicic acid in contrast to carbon colloids. Through its physical structure and chemical stability silic acid can assert itself in the organism and in contrast to the organic colloids, it is not susceptible to splitting. To a certain extent they are a counterpole of the organic. They are found especially where the chemical metabolism is low or has ceased. Thus silicic acid will be taken up an transported as a foreign body by the phagocytes and will be found for the most part in the hair and nails in solid form, otherwise it is precipitated chiefly in the connective tissue of the body and always where the organic metabolism is at a minimum. One finds the ever present SiO2 in traces in all tissues and excretions; since it is present in dust it can be removed only with difficulty in analysis. The marked silicic acid content of the bronchial glands of millers who inhale much SiO2 with flour dust, shows transportation via the lymphatic ways.
an especial enrichment of silicic acid in the pancreas has been asserted. The pancreas is said to be a site of strong of silicic acid. But from the analysis of these authors themselves, the amount of silicic acid in the pancreas is not greater than that found in other organs. Hugo Schulz has definitely contradicted the above assertion through numerous analysis.
STIMULATION OF FIBROBLASTS
Kobert would conclude from quantitative studies on healthy and tuberculous lungs that silicic acid participates in the healing of tuberculous foci, and that deficient silicic acid prevents healing. But a survey of numerous quantitative studies of French and German authors shows that this deficiency theory is not maintainable. If silicic acid is used in the tuberculous lung, then it is not as a nutritive substance but as an excitor of connective tissue growth. For this the experimental investigations of Kahle and Rossle are of great significance. They found that the administration of silicic acid preparations, 0.5-2.0 g. daily, in experimentally produced tuberculosis of guinea pigs, in and around the tubercle formation a new connective tissue, distinct encapulation and gradual scarring off the tuberculous tissue; it occured entirely in the manner of scaring in tuberculous foci in man. With 0.5g. (per os) the connective tissue of loose fibres, with 2.0 grams in solid fibres. Rossle recognizes in sick guinea pigs even on the 5th day of treatment with silicium a suddenly awakened fibroplastic activity of the tubercle. Likewise after silica acid treatment in experimental animals with tuberculous livers, an actual cirrhosis with new formation of billiary passages develops. New growth is also observed in the tuberculous spleen connective tissue. Outside of Rossle, Gye and Purdy demonstrated a fibrous inflammation of the liver, spleen and kidney with small doses of colloidal silicic acid.
With this the possibility of excitation of fibroplastic activity in the animal tissues is accomplished and with such a relatively crude basis of manner of action of a medicinal substance, one can hardly make a transition to the human organism. According to Rossle’s report siliciium has a great significance for the defense against destructive tuberculosis and porcelain workers who inhale the fine dust of silicates, if they become tuberculous, have for the most part the fibrous form of disease. And this fibroid-indurative form is more favorable than the exudative-ulcerative form as is well known.
One may present the following conception of the effectiveness of silicic acid on connective tissue formation in the lung. In crushed stone workers the fragments of stone are in acrude and hardly dispersed state. They reach the lungs and in their transportation to the lymph glands produce relatively crude scars with subsequent connective tissue growth, the so-called chalicosis pulmonum. How greately this gives the first occasion for the outbreak of pulmonary tuberculosis is known and easy to understand. The same behaviour occurs with the finer silicic acid-rich dust which millers inhale in large amounts. Also by the copious ingestion of slightly dispersed silicic acid they are not protected against pulmonary tuberculosis. But it is otherwise with the medicinal administration of silicic acid. The Glashager mineral springs, which were preferred by Kobert, contain silicic acid in a dilution of 5:1,000,000. Here one can imagine much better that the particles of silicic acid are sufficiently small in order to provoke scarring only in single cells with which they come in contact, that is, on the whole, in the cells which have the capacity to stimulate fibroplastic activity. How fine we must represent the colloidal process in actuality we whall still see in discussing the actions of silicic acid on the blood cells. From the discussion up to the present we may also conclude that silicic acid in cases of tuberculosis, where a stimulation of the fibroplastic activity of the cells seems necessary, should serve as a medicinal supportive agent for the self healing but that the chief factor outside of the correct selection of the remedy, is the selection of the right degree of division since from too slight a grade of dispersion more harm than good may be expected.
USE IN PULMONARY TUBERCULOSIS
Since most of the therapeutic trials with silicic acid, outside of homoeopathy, have been arranged in pulmonary tuberculosis, the results should be mentioned here briefly. The trial was carried out by the Kobert school, particularly by Kuhn. He employed in part the Glashager mineral spring, partly a tea from the silicic acid-rich plants and indeed Equisetum minor, polygonum aviculare, galeopis ochroleuca. The therapy was continued over a long time. But since a complete series of physical-dietetic measures were employed simultaneously and on the other side medicinal measures were used, at most only a general impression can be gained from these studies on the addition of silicic acid tea to the other methods of treatment; but these seemed favorable in pulmonary tuberculosis, especially at the beginning of the disease. Naturally it does not awaken much confidence when Kuhn did not venture to remove other medicinal therapy even if only experimentally. Indefinite impressions from the use of teas of plants strong in silicic acid were available from the centuries-old use of plants as tuberculosis teas as well as under other names in folk medicine. From an employment on a general diagnosis one cannot expect much more than uncertain impressions.
COLLOID ACTIONS ON SERUM AND CELLS
The experiments with colloidal silicic acid on serum and cells has brought many explanations for the possibility of action of finely divided silicic acid.
Investigations with sodium silicate have shown that in a dilution of 1:1000 it precipitates proteins and agglutinates red blood cells. In this respect colloidal silicic acid agglutinates red blood cells in a dilution which corresponds to the 7 decimal potency of silicic acid. The other conditions such as the presence of electrolytes have the same influence as with organic agglutinins. Hemo-agglutination occurs most rapidly with the medium concentrations, in higher concentrations it is slowed. It is activated similarly as organic agglutinins by warming, the agglutinating action will be removed by prolonged standing in a 1 Percent sodium chloride solution containing silicic acid, more rapidly through moderate warming or brief boiling, whereby with sufficient dilution of the fluid no noteworthy alterations are shown. With the hemo-agglutination by silicic acid, an easy destructibility of the red blood cells is also shown, for example, even with mild warming with a 1 Percent salt solution a certain amount of hemoglobin is given off and the same occurs with shaking. Now silicic acid does not indifferently agglutinate all cells. It has a certain grade of specificity even if the immunohemolysins will not, for example, agglutinate the typhoid bacillus. On the other hand it acts agglutinating and paralyzing in still smaller concentrations on spermatozoa. After red blood cells are agglutinated by silicic acid, the addition of a very dilute lecithin solution causes hemolysis and the outpouring of hemoglobin. (In strong concentrations lecithin alone will produce hemolysis.) Thereby a greater amount of silicic acid than the necessary one will delay or prevent hemolysis. We see also for this biochemic action as so often a definite optimum is present and is a sign of a colloid reaction. At the same time this is ever again proof that it requires a definite dose which does not pass beyond a certain amount in order to obtain definite biologic results. The hemolysis which results in rabbit blood cells from agglutination by silicic acid also occurs by the addition of fresh rabbit serum; but not or in a higher degree if the serum has been previously heated for a short time to 60o. The action of the srum addition (that is, complement) can be suppressed or depressed in silicic acid hemolysis by the same agent as in the other cell dissolving action of sera. Landstiener represents the hemolysis as an alteration in the lipoid part of the blood cells (or the lipoid- protein compounds) forming the pre-condition so that through the intermediation of silicic acid more lecithin or complement will be absorbed by the blood cells. Lecithin solution alone with silicic acid solution forms a very slow falling precipitate which rapidly unites into flocculates when a 1 Percent mixture of sodium chloride is added. A Siegfried has found, silicic acid also produces a precipitate in the blood serum. This precipitation will be depressed by an excess of the blood serum, similar to the precipitating effect of precipitins.
v.Dungern and Coca also found that a moderate concentration of silicic acid represented the optimal condition for the hemolytic action. Not only with an increase in the silicic acid but also in increase of the blood serum the hemolysis decreases. The same happens from the addition of certain salts, as magnesium, calcium and barium chloride. Since silicic acid also unites with substances of the blood serum, it may be assumed that in the mixture with the complement containing serum, part of the silicic acid and part of the complement in the serum will become inactive. This has been confirmed in that it makes a difference in the hemolysis whether one adds the silici acid first to the blood cells or adds the srum previously. The hemolysis will naturally be promoted by the previous addition to the blood cells. Now while the blood cells are undoubtedly made much more sensitive to complement and lecithin through silicic acid, v. Dungern and Coca found that in contrast to other substances, they become more resistant to soap solution. The alteration of the state of the blood cells by silicic acid must therefore be a particular one.
Seligmann found that the reaction playing between two colloids or between one colloid and a salt can lead to flocculation and even if this is not visible. Hailer showed that 1-5 Percent poured into guinea pig serum bound the complement entirely or in part so that the addition of sensitized blood was either not at all or only incompletely dissolved. On the countrary a coagulating ferment from a rennet solution was not adsorbed by silicic acid. Accordingly ferments behave otherwise than the complement of the serum. Rennet will be bound just as little by silicis acid as a specific precipitate as occurs in the reaction between antigen and immune body. Silicic acid also behaves entirely as a specific precipitate in the reaction between antigens and immune bodies. For the different behavior of complement and rennet ferment in the two cases, different adsorption coefficients of the two substances are made responsible, as occurs in other cases. The difference of specificity between the precipitate formation of antigen and immune body on the one side and an inorganic colloid will not rest there on. It is merely shown that also in this specific action, a decisive weight is to be place on colloidal flocculation. Landsteiner and Bock found that the silicic acid of a so-called hemolytic system could appear in place of specific immune bodies, of hemolysins and that such a non-specific hemolytic system could be used as a test object in the Wassermann test for syphilis. But now Landsteiner employed the active serum of the patient, also his immune body and his complement and also his own blood cells as a test object. From this it proceeds that the silicic acid in the human blood works hemolytically. But this method differs from the usual arrangement in the Wassermann test because in it guinea pig serum is employed as complement and sheep bloodcorpuscles tend to be employed as an indicator. Liebers found also the usual arrangement of the hemolytic system in which the specific hemolysin was replaced by silicic acid could not be used. Hemolysis did not appear in either negative or positive sera. In the contest around the complement of the guinea pig srum, even in the usual test arrangement the combination of the luetic liver extract and the luetic immune body, in the complement binding endeavor the silicic acid was the victor. In his studies Liebers found that silic acid did not produce hemolysis in all kinds of blood, for example not in sheep and horse blood, but on the other hand in rabbit and swine blood. Also in the testing of various types of sera, that is complements, one of which had been sensitized by a specific immune body (hemolyis), the other by silicic acid, he found an extensive parallelism in the action of specific bodies and the silicic acid. The fact that different types of blood cells absorb silicic acid differently is explained by Liebers as due to different surface tensions, for which the different chemical composition of single types of blood can be made responsible. Furthermore other types of investigations make it seem probable that the various grades of alkalescence of the blood corpuscles may play a role. Silicic acid alone acts agglutinating on the red blood cells according to Liebers but does not affect hemolysis. Older silicic acid solutions which have become slightly turbid and which therefore have a slighter grade of dispersity are less useful for showing the hemolytic effects but still produce marked agglutination. With this agrees the fact that smaller amount of silicic acid of a higher grade of dispersity provides the most favorable chance for the hemolysis. Here also we again see how the grade of dispersion of the silicic acid is of striking importance for the type of biochemic action. In agreement with the earlier findings of v. Dungern and Coca, Nathan later found that sheep blood by a treatment with silicic acid has increased resistance against the hemolytic actions of saponins, indeed it becomes more sensitive for certain materials but insensitive for others.
Alteration of the colloidal state nowadays is made responsible for the process of hemolysis, and complement formation. According to Sachs complement activation is effected by an alteration of the state of the serum globulin, which need not exceed a certain step. Also according to him the complement effect in the presence of red blood cells will be released by a physical influence on the complement containing serum in the sense of a decreased dispersity of the globulin. Sachs ascribed to the physical state of the serum respectively its globulins, a very special significance for pathology and therapy. The complicated relations which exist on the introduction of colloidal silicic acid into the blood depend upon the already many times cited simultaneous action of the blood cells and the serum constituents. Sachs expresses this as follows;: “It is striking that non-specific substances (such a silicic acid) which are suitable for intermediating in complement action can also act anti-complementary. It simply amounts to the question whether the agents concerned are simultaneously mixed with blood cells and complement or whether the complement is mixed and then the blood added. In the first case the hemolysis appears and in the last case not, and indeed also when one has sought to intermediate through specific amboceptors. Likewise sodium silicate cannot convert a non-hemolytic system in to a hemolytic one. New pipettes which are used to measure a negative serum make this positive.