106 Dr. Proat on the Changes in the fixed Principles [Feb. 



Water 170-2 



Albumen* 55*3 



Yellow oil 91-0 



316-5 



" But I have reason to believe that the proportions of these 

 ingredients differ a little in different eggs." 



Experiments on the Egg at the End of the first Week of Incuba- 

 tion, or about the 8th Day. 



At the end of the first week, it was found, on an average, that 

 the egg had lost about 50 grains in the 1000, and the weights of 

 its constituent principles in their moist state, were as follows : t 



Unchanged albumen 232*8 



Modified albumen 1 79-8 



Liq. amnii, membranes, blood vessels, &c. . 07-0 



Animal 22-0 



Yelk 301-3 



Shell and loss 167-1 



1000-0 



Dr. Prout here makes the following brief remarks on the 

 general phenomena presented by the different constituent prin- 

 ciples of the egg at those periods at which it has been submitted 

 to examination. 



" It has been remarked by many observers, that soon after the 

 process of incubation has commenced, the yelk becomes more 

 fluid than usual; and that as the liquor amnii increases, that 

 portion of the albumen occupying the upper and larger end of 

 the egg, begins to assume a peculiar appearance. In the pre- 

 sent experiments (in which the egg was always previously boiled), 

 the liquor amnii and portion of albumen in question, at the period 

 now under consideration, exhibited somewhat the appearance of 

 curds and whey. Nor did the analogy consist in mere appear- 

 ance ; for the curdy-looking matter, which was of a yellow 

 colour, and which I have termed modified albumen, resembled 

 the curdy part of milk in its properties, so far as to contain inter- 

 mixed with it an oily or butyraceous principle. A portion of 

 this oily principle, on being separated and examined, was found 

 to be soluble in alcohol, of a bright yellow colour; and, in short, 



* " This proportion of the albuminous principle does not differ much from that stated 

 to exist in the yelk of the common fowl, by Mr. Hatchett. Philos. Trans, vol. cvi. 

 p. SOH." 



+ In the original paper, the weights of the constituents of two eggs are here given ; 

 the same is the case with the following series of experiments, and with all the remaining 

 analyses except two ; but as no striking differences are thus presented, only one of each 

 kind is given in this abstract. 



