Muscular and Pulmonary Tissues. 455 



1st. That there is a safe ground for the belief that the elemen- 

 tary physical constitution of muscle, and of other animal tissues, 

 is similar to that of a jelly — with this difference, that it is an 

 organized jelly whose fibrinous or cellular form gives it due tena- 

 city for the performance of its functions ; but its water, albumen, 

 and other constituents appear to hold the same physical relation 

 to each other as would water to gelatine in jelly. 



2nd. That all tissues are formed of three different classes of 

 substances, namely : — those which constitute the ripe tissue, or 

 the portion of the tissue insoluble in water ; next, those constitu- 

 ting the nutritive material of the tissue, which are soluble in 

 water and colloid ; and, finally, those of which the eff"ete material 

 is formed ; they are soluble in water, crystalloid, and difi"usible. 

 3rd. That the nutritive material and ripe tissue have the same 

 chemical composition, so that the mature tissue is merely an 

 organized form of the nutritive material, the change being purely 

 morphological. 



4th. That in muscular tissue the whole of the phosphoric acid 

 is eliminated under the form of a neutral tribasic phosphate of pot- 

 ash. Liebig has shown by chemical tests, in his admirable work on 

 the Chemistry of Food, that this compound really exists in flesh ; 

 but the result of my inquiry is that the whole of the phosphoric 

 acid and potash are eliminated in the proper proportions to form 

 exactly either a neutral tribasic phosphate or a pyrophosphate of 

 potash ; while at the same time there exist in flesh certain 

 quantities of phosphoric acid and potash which are not in the 

 proportion of a phosphate, and take part in the actual formation of 

 the mature tissue. This is, I believe, the first time it has been 

 shown with mathematical accuracy by a physiological mode of 

 reasoning, if I may so express it, how substances are brought 

 together and combine in obedience to those laws which regulate 

 and maintain the phenomena of life. 



5th. That the albuminous constituents of muscular tissue 

 appear to be eliminated, in the process of waste, under the form 

 of kreatine, kreatinine, and other crystalloid substances. 



6th. That blood yields to flesh considerably more potash than 

 is required for the formation of muscular tissue, the excess being 

 necessary for the elimination of the phosphoric acid by converting- 

 it into a crystalloid phosphate. 



7th. That the nutrition of pulmonary tissue difi'ers from that 

 of muscles, from the parenchyma or substance of the lungs con- 

 taining a much larger proportion of nutritive material and much 

 less waste, showing apparently that the tissue of the lungs under- 

 goes a more rapid nutrition than that of the muscles. 



8th. That while in muscles the phosphoric acid and potash 

 are eliminated in the form of a crystalloid phosphate, in pulmo- 



