Edmund Drechsel

“ The chemistry of the animal body is not simply confined to the formation and decomposition of definite chemical compounds; the organism also makes use of certain physical phenomena which are inseparably connected with the chemical, namely, the electric and the thermic. ”

“ Numerous experiments, in which the amount of substances taken up and excreted by the organism were determined, have given valuable results, but not in regard to the reactions taking place in the body. The chemistry of the living body shows the peculiarity that all reactions take place at the temperature of the body, which is quite low, without the intervention of strong reagents in the ordinary sense. ”

“ Here is a field in which chemistry must cultivate independently, not as the servant of physiology, for the fruits of the labor will be of equal value to both sciences. Whatever difficulties this problem may produce, we are certain that its solution is within our reach. ”

“ The decomposition of carbonic acid by the influence of the light and heat of the sun is effected in such a manner that the carbon is employed in the formation of the compounds of which the plant is built up, while the oxygen escapes into the atmosphere., Now, we know that solids contain the least energy, because it must be supplied to them in the form of heat in order to convert them into the liquid or gaseous state, while, on the contrary, heat must be withdrawn from gases to condense them to liquids or solids. ”

“ If we wish to produce similar reactions outside of the organism, we generally employ a high temperature and substances which would destroy the organism itself. For instance, to prepare hippuric acid from benzoic acid and glycocol, in the laboratory, it is necessary to heat both for some time to 160°, while in the body it is only necessary to dissolve them in blood, and pass the solution through a kidney, when a combination is effected. ”

“ Above all, it is to be emphasized that within each living cell a number of chemical processes are constantly taking place simultaneously, all of which are necessary for the existence and vitality of the cell. These processes are of so different a nature that it is difficult to believe that they take place within a perfectly homogeneous mass. It seems much more simple and natural to suppose that each of the reactions takes place separately, which could be most readily effected by an internal organization of the cell. ”

“ We must make our experiments at the temperature of the body, we must employ no reagents whose presence would be injurious to the organism, we must also take into consideration that we may not he able to attain our object by a single process, but by a whole series of altogether different processes—only by a most careful observation of all these points can we arrive at results which will allow us to draw conclusions with reference to the corresponding processes in the body. ”

“ All such complicated compounds, having a high molecular weight, are capable of furnishing very different products of decomposition under slightly modified conditions. If, therefore, the decompositions in the organism should always take place in the same manner, the governing conditions must be exceedingly constant. Every product of decomposition, which is not to be directly excreted, is further employed in the organism, and exerts an influence on the chemical processes taking place, and may therefore produce disturbances in them. ”

“ These processes of fermentation have an extraordinary distribution, for not only do the individual living cells produce ferments, but also those which form parts of complicated organisms. This is especially the case with those cells which are often united in enormous quantities to form a larger organ. I will recall the salivary gland, the peptic gland, and the pancreas, whose secretions are exceedingly rich in ferments. This is of the greatest importance for the economy of the animal organism, since it permits a considerable performance with a comparatively small expenditure of means. ”

“ Although we have been taught, by the celebrated discovery of the artificial production of urea by Wöhler, that the compounds occurring in the organism may also be produced out of the body, this and similar experiments have given no explanation of the manner in which the reaction takes place in the organism. ”

“ WHEN the science which endeavors to determine the phenomena of life and their connection was enabled to employ more exact expedients for its observations, the influence which the chemical process exerts on that of life became known. ”

“ A fungus, the so-called yeast, converts the sugar into glucose, and then decomposes this into alcohol and carbonic acid, with the simultaneous formation of small quantities of other products, such as succinic acid, glycerine, etc. The amount of yeast is not increased unless other substances, particularly nitrogenous organic and certain inorganic salts required in building up the body of the cells, are present. ”

“ For, even where the best methods of chemistry are deficient, we meet with phenomena, the appearance of which can only be explained by chemical decomposition. The substances of which the muscle is formed and the manner in which they are arranged are still imperfectly known; of the chemical process which takes place in the sarcous elements, when a muscle passes from rest to the contracted state, we know scarcely anything ”

“ The physical apparatus of the body are preserved in the aggregate state and form, which are necessary for the performance of their functions by a definite chemical composition of the organs and the fluids which saturate them; and the source of the power required by the living body for its movements is to be sought for in the destruction of the compounds of which it is composed. ”

“ Though we must confess that our knowledge of the chemical processes in the animal body is still very incomplete, we must recognize that the investigations made in this direction have given us much information. Though the substances which react on each other are known in the fewest cases, we have obtained hints regarding the manner in which they react. ”

“ Similar relations exist in the animal body; here we also find the constituents in a definite arrangement which we term organization, and by means of which the body has control over such peculiar conditions that we can not, or at best only in rare cases, imitate them in the laboratory, and produce the same reactions as are produced by the body. ”

“ But neither of these hypotheses is tenable: for, on the one hand, no chemist has ever obtained cyanic acid by the oxidation of nitrogenous substances under the conditions which are found, or may at any rate be assumed, in the organism; on the other hand, the ammonium carbonate which is introduced with the food can not be resorbed as such, for it is decomposed by the acid juices of the stomach, neither can this substance be formed in the organism from carbonic acid and ammonia. ”

“ Hence the chemical processes within the living cell are of two kinds: those in which ferments take part, and those in which they do not. The ferments are definite chemical compounds, which are able to decompose large quantities of other substances without undergoing any apparent change themselves. ”

“ If we accept this, and consider the occurrence of substances still unknown, and present, perhaps, only in very small quantity in the animal organism, we will obtain a hint as to the explanation of effects which many foreign substances produce, though in very small quantities, on the organism. ”

“ Not that we have here progressed any further than elsewhere, but we have attained the certainty that the most important processes take place in the cells themselves, and that substances are formed which are able to produce powerful chemical changes. ”

“ As our knowledge of these poisons has increased, we have found that they never act on the whole organism, but always on particular organs or groups of organs; these may be the nerves, the muscles, the glands, or only a portion of them. While the curarine paralyzes all voluntary muscles, the heart perceives nothing of its effects ”

“ The latter assumption is the most probable, for it will make it readily perceptible that the reaction takes place in an aqueous solution. If it is asked in what manner the oxygen and the hydrogen may be removed from the ammonium carbonate, the simplest answer will be that the hydrogen is removed by oxidation and the oxygen by reduction. ”

“ They have an ephemeral existence only, but are, nevertheless, of the greatest importance in the economy of the whole. Most of them are unknown to us, but in some cases they have been successfully isolated. ”

“ At present we may say, that which is ponderable can be weighed, and that which proves to be an individual can be isolated. After, however, the analysis is once completed, synthesis will be close at hand. ”

“ Wherever matter is found definitely arranged, it is also accompanied by effects dependent upon the arrangement; platinum, zinc, and sulphuric acid, when connected in a proper manner, form a galvanic element and give rise to a galvanic current. ”