MUSCLE .AND EXTRACTIVES. 343 



approximate composition. In the calculation carbonic acid is 

 not considered. The table below is from the Konig collection. 



K 2 O 37-04 



Na 2 O 10.14 



CaO 2.42 



MgO 3-23 



Fe 2 O 3 0.44 



P 2 O 5 41.20 



SO 3 0.98 



Cl 4.66 



SiO 2 0.69 



From the table it appears that potassium phosphate is the 

 most abundant substance in the ash. Much of this doubtless 

 preexists in the muscle juices, while a small portion is of 

 oxidation origin. The small sulphate content is probably due 

 to protein sulphur fully oxidized in the combustion. In the 

 past too little attention has been given to the mineral constitu- 

 ents of the body, it being commonly assumed that they repre- 

 sent " waste " or " ash " only. But the newer applications of 

 chemistry, especially physical chemistry, to physiology have 

 disclosed the fact that the inorganic salts are especially con- 

 cerned in the proper maintenance of many of the body func- 

 tions. The balanced osmotic pressure of the body fluids is 

 largely a function of the salt content, and variations here are 

 of great importance. The mineral salts are the carriers of 

 electric charges in the body and as such seem to have im- 

 portant duties to perform. 



EXTRACT OF MEAT. 



By boiling lean meat with water the soluble constituents are 

 dissolved, producing an extract. When this is concentrated 

 to a paste the article known commercially as " Extract of 

 Meat " results. The article was first made in quantity in 

 South America to utilize the carcasses of cattle slaughtered 

 for the hides, but later the manufacture was introduced else- 

 where, and generally to utilize certain waste or by products in 

 the meat industries. At first the extract was assumed to pos- 



