Gelatine. 171 



The bones used for this purpose are those only which 

 answered no useful purpose (except for the fabrication of 

 phosphorus or ammoniac) before this discovery, such as those 

 of the head, the ribs, &c. &c., the legs of sheep and calves, &c. 

 Those formerly used by toysmen {Tableiiers) are still used foe 

 that purpose, after extracting so much of the gelantine as can 

 be done by ebullition. 



When the heads of oxen are to be operated upon, they 

 begin by extracting the teeth, (these are reserved for the 

 fabrication of ammoniac, as affording a greater proportion of 

 that alkali than. any of the other bones,) they then break the 

 skull, in such manner as to preserve all the compact parts in 

 as regular forms as possible ; these pieces present a surface 

 of 20 to 30 square inches, and are put to soak in a mixture of 

 muriatic acid and water. The muriatic acid used bears about 

 twenty-three degrees o^ the aerometre, and is diluted by 

 water to about six degrees — four parts of the liquor is used to 

 one part of boues. They are left in this state, in open ves- 

 sels, until a complete solution of the phosphate of lime has 

 taken place, and the gelatinous part of the bone remains in 

 its original shape and size, and is perfectly supple. When 

 this operation is finished, which commonly lasts six or eight 

 days, the gelatine is put into baskets, being first drained, and 

 immersed a short time in boiling water, in order to extract 

 any small remains of grease, which would deteriorate the 

 gelatine, and also to extract any of the acid which might be 

 lodged in the pores. It is then carefully wiped with clean 

 linen, and afterward washed in copious sti'eams of cold water, 

 to whiten it, and render it more transparent ; it is then put to 

 dry in the shade. 



Two ounces of this gelatine are said to be equal to three 

 pounds of beef in making soup — that is, three founds of beef and 

 two ounces ofgelatine will make as much soup, and of as good 

 quality, as six pounds of beef. It is constantly used in some of 

 the hospitals of the capital, particularly in the lying-in-hospital. 



The ends of the bones, and such parts as from their porosity 

 might still retain a portion of the acid, are separated, and used 

 for ntaking glue of a very superior quality. 



16* 



