COMPOSITION OF NERVOUS MATTER. 



59 



as they point out the way which chemistry 

 pursues,, and which she ought not to quit, 

 if she would really be of service to phy- 

 siology and pathology. The combinations 

 of the chemist relate to the change of mat- 

 ter, forwards and backwards, to the con- 

 version of food into the various tissues and 

 secretions, and to their metamorphosis into 

 lifeless compounds ; his investigations ought 

 to tell us what has taken place and what 

 can take place in the body. It is singular 

 that we find medicinal agencies all de- 

 pendent on certain matters, which differ in 

 composition; and if, by the introduction of 

 a substance, certain abnormal conditions are 

 rendered normal, it will be impossible to reject 

 the opinion, that this phenomenon depends 

 on a change in the composition of the consti- 

 tuents of the diseased organism, a change in 

 which the elements of the remedy take a 

 share ; a share similar to thtvt which the vege- 

 table elements of food have taken in the for- 

 mation of fat, of membranes, of the saliva, 

 of the seminal fluid, &,c. Their carbon, hy- 

 drogen, or nitrogen, or whatever else belongs 

 to their composition, are derived from the 

 vegetable organism ; and, after all, the action 

 and effects of quinine, morphia, and the 

 vegetable poisons in general, are no hypo- 

 theses. 



95. Thus, as we may say, in a certain 

 eense, of caffeine, or theine, and asparagine, 

 &c., as well as of the non-azotized elements 

 of food, that they are food for the liver, 

 since they contain the elements, by the pre- 

 sence of which that organ is enabled to per- 

 form its functions, so we may consider 

 these nitrogenized compounds, so remark- 

 able for their action on the brain and on the 

 substance of the organs of motion, as 

 elements of food for the organs as yet un- 

 known, which are destined for the meta- 

 morphosis of the constituents of the blood 

 into nervous substance and brain. Such 

 organs there must be in the animal body, 

 and if, in the diseased state, an abnormal 

 process of production or transformation of 

 the constituents of cerebral and nervous mat- 

 ter has been established ; if, in the organs in- 

 tended for this purpose, the power of form- 

 ing that matter out of the constituents of 

 blood, or the power of resisting an abnormal 

 degree of activity in its decomposition or 

 transformation, has been diminished; then, 

 in a chemical sense, there is no objection to 

 the opinion, that substances of a composi- 

 tion analogous to that of nervous or cerebral 



matter, and, consequently, adapted to form 

 that matter, may be employed, instead of 

 the substances produced from the blood, 

 either to furnish the necessary resistance, or 

 to restore the normal condition. 



96. Some physiologists and chemists have 



expressed doubts of the peculiar and dis- 

 tinct character of cerebric acid, a substance 

 which, from its amount of carbon and 

 hydrogen, and from its external characters, 

 resembles a nitrogenized fatty acid. But a 

 nitrogenized fat, having an acid character, 

 is, in fact, no anomaly. Hippuric acid is in 

 many of its characters very similar to the 

 fatty acids, but is essentially distinguished 

 from them by containing nitrogen. The 

 organic constituents of bile resemble the 

 acid resins in physical characters, and yet 

 contain nitrogen. The organic alkalies are 

 intermediate in their physical characters be- 

 tween the fats and resins, and they all con- 

 lain nitrogen. A nitrogenized fatty acid is 

 as little improbable as the existence of a 

 nitrogenized resin with the characters of a 

 base. 



97. An accurate investigation would pro- 

 bably discover differences in the composition 

 of the brain, spinal marrow and nerves. 

 According to the observations of Valentin, 

 the quality of the cerebral and nervous sub- 

 stance is very rapidly altered from the period 

 of death, and very uncommon precautions 

 would be required for the separation of 

 foreign matters not properly belonging to 

 the substance of the spinal marrow or brain. 

 But, however difficult it may appear, the 

 investigation seems yet to be practicable. 

 We know, in the meantime, that all expe- 

 rience is against the notion of a large 

 amount of carbon and hydrogen in the sub- 

 stance of the brain. The absence of nitro- 

 gen as an element of the cerebral and 

 nervous matter, appears, at all events, im- 

 probable. This substance, moreover, can- 

 not be classed with ordinary fats, because 

 we find the cerebric acid combined with 

 soda, whereas, all fats are compounds of 

 fatty acids with oxide of glycerule. In re- 

 gard to the phosphorus of the brain, we can 

 only guess as to the form in which the phos- 

 phorus exists. "Walchner observed recently 

 that bubbles of spontaneously inflammable 

 phosphuretted hydrogen were disengaged 

 from the trough of a spring in Carlsruhe, 

 on the bottom of which fish had putrefied ; 

 and gases containing phosphorus have also 

 been observed among the products of the 

 putrefaction of the brain.* 



* The curator of the museum at Geneva gave 

 to M. Leroyer,. apothecary, a large quantity of 

 spirit of wine, which had been used for the pre- 

 servation cf fishes, and which he undertook to 

 purify. He distilled from it a mixture of chloride of 

 calcium and quicklime, and evaporated the residue 

 in the air, over a fire. As soon as the mass had 

 acquired a certain consistence, and a higher tem- 

 perature, a prodigious quantity of spontaneously 

 inflammable phosphoretted hydrogen was dia- 

 engaged. (Du.nas. V. 267.) 



