-364 THE FLUIDS OF THE EGG. 



in order to determine with accuracy the quantity of 'the true 

 albumen in the white of egg, a quantity of the latter (perfectly 

 fresh, and weighed in a closed vessel) must be carefully triturated 

 in a mortar; the watered \vhite of egg is then to be poured into a 

 cylindrical glass, and to be diluted with fifteen or twenty times its 

 quantity of water. Without this very free dilution, the albuminous 

 solution can hardly be filtered, and even then it will often not pass 

 through the filter in summer at a high temperature, when formations 

 of byssus and vibriones so readily occur. After the whole of the 

 fluid has been placed upon the filter, it is adviseable at once to treat 

 the residue with an aqueous solution of hydrochlorate of ammonia, 

 and then to thoroughly wash it. The hydrochlorate of ammonia 

 not merely dissolves the albumen which was precipitated by the 

 water, but it likewise has the effect of allowing the \vhole of the 

 albumen to coagulate on subsequently boiling the filtered fluid ; 

 it supersedes the acetic acid that is generally recommended, 

 since there are formed chloride of sodium and albuminate of 

 ammonia, which latter parts with its ammonia on boiling, perfectly 

 coagulates, and forms a coagulum which may be readily collected 

 on a filter. 



The fat of the white of egg, like the extractive matters and the 

 sugar, must be detected and quantitatively determined by the 

 methods which have been already described in their appropriate 

 places. 



The presence of pre-formed alkaline carbonates can only be 

 determined by the same method which has been already described 

 as applicable to the blood and to transudations (see p. 328) ; when 

 they have been determined, we may readily find a means of calcu- 

 lating the quantity of alkali in comhination with albumen. Un- 

 fortunately, however, in consequence of the varying proportions in 

 which the alkaline carbonates, and the alkali in combination with 

 albumen, exist in different eggs, the determinations that have been 

 made are so various, that as yet we have not succeeded in deter- 

 mining a definite ratio of the alkali to the albumen, or of the 

 alkaline carbonates to the albuminate of soda. 



The analysis of the yolk also presents its difficulties, some of 

 which cannot be altogether overcome. The yolk-corpuscles are 

 the less easily separated mechanically from the rest of the fluid, in 

 consequence of the simultaneous presence of free granules of 

 jundissolved vitellin and fat-globules. I have found the fol- 

 lowing to be the best method of proceeding with the analysis; 

 as in the examination of animal fluids generally, we must first 



