ORGANIC CHEMISTRY 



APPLIED TO 



PHYSIOLOGY AND PATHOLOGY. 



I. IN the animal ovum, as well as in the 

 eeed of a plant, we recognise a certain re- 

 markable force, the source of growth, or in- 

 crease in the mass, and of reproduction, or 

 of supply of the matter consumed; a force 

 in a state of rest. By the action of external 

 influences, by impregnation, by the pre- 

 sence of air and moisture, the condition of 

 static equilibrium of this force is disturbed ; 

 entering into a state of motion or activity, 

 it exhibits itself in the production of a series 

 of forms, which, although occasionally 

 bounded by right lines, are yet widely dis- 

 inct from geometrical forms, such as we ob- 

 serve in crystallised minerals. This force is 

 called the vital force, or viz vitce vitality. 



The increase of mass in a plant is deter- 

 mined by the occurrence of a decomposition 

 which takes place in certain parts of the 

 plant under the influence of light and heat. 



In the vital process, as it goes on in 

 vegetables, it is exclusively inorganic matter 

 which undergoes this decomposition ; and 

 if, with the most distinguished mineralo- 

 gists, we consider atmospherical air and 

 certain other gases as minerals, it may be 

 said that the vital process in vegetables ac- 

 complishes the transformation of mineral 

 substances into an organism endued with 

 life ; that the mineral becomes part of an 

 organ possessing vital force. 



The increase of mass in a living plant 

 implies that certain component parts of its 

 nourishment become component parts of 

 the plant; and a comparison of the chemical 

 composition of the plant with that of its 

 nourishment, makes known to us, with 

 positive certainty, which of the component 

 parts of the latter have been assimilated, and 

 whicn have been rejected. 



The observations of vegetable physiolo- 

 gists and the researches of chemists have 

 mutually contributed to establish the fact, 

 that the growth and development of vege- 

 tables depend on the elimination of oxygen, 

 which is separated from the other compo- 

 nent parts of their nourishment. 



In contradiction to vegetable life, the life 

 of animals exhibits itself in the continual 

 absorption of the oxygen of the air, and its 

 combination with certain component parts 

 of ihe anirna^ body 



While no part of an organized being can 

 serve as food to vegetables, until, by the 

 processes of putrefaction and decay, it has 

 assumed the form of inorganic matter, the 

 animal organism requires, for its support 

 and development, highly organized atoms. 

 The food of all animals, in all circum- 

 stances, consists of parts of organisms. 



Animals are distinguished from vegeta- 

 bles by the faculty of locomotion, and, in 

 general, by the possession of senses. 



The existence and activity of these dis- 

 tinguishing faculties depend on certain in- 

 struments which are never found in vegeta- 

 bles. Comparative anatomy shows, that 

 the phenomena of motion and sensation de- 

 pend on certain kinds of apparatus, which 

 have no other relation to each other than 

 this, that they meet in a common centre. 

 The substance of the spinal marrow, the 

 nerves, and the brain, is in its composition, 

 and in its chemical characters, essentially 

 distinct from that of which cellular sub- 

 stance, membranes, muscles, and skin are 

 composed. 



Every thing in the animal organism, to 

 which the name of motion can be applied, 

 proceeds from the nervous apparatus. The 

 phenomena of motion in vegetables, the 

 circulation of the sap, for example, observed 

 in many of the characeae, and the closing ot 

 flowers' and leaves, depend on physical and 

 mechanical causes. A plant is destitute of 

 nerves. Heat and light are the remote 

 causes of motion in vegetables ; but in ani- 

 mals we recognise in the nervous apparatus 

 a source of power, capable of renewing 

 itself at every moment of their existence. 



While the assimilation of food in vegeta- 

 bles, and the whole process of their forma 

 tion, are dependant on certain external in 

 fluences which produce motion, the deve 

 lopment of the animal organism is, to a 

 certain extent, independent of these external 

 influences, just because the animal body 

 can produce within itself that source of mo- 

 tion which is indispensable to the vital pro- 

 cess. 



Assimilation, or the process of formation 

 and growth in other words, the passage of 

 matter from a stato of motion to that of rest 

 goes on in the same way in animals and 



