in the fixed principles of the egg during incubation. 3 79 
uniformly during a very long period.* The loss appears to 
be somewhat greater in summer than in winter, owing, doubt- 
less, to the difference in temperature, which, in the present 
instance, varied from 40° to 70°. On being broken, the whole 
of the contents of this egg were found collected at the 
smaller extremity in a solid state, but on being put into 
water, they absorbed a large portion of that fluid, and as- 
sumed an appearance not much unlike those of a recent egg ; 
the smell also was perfectly fresh. 
The relative weights of the shell, albumen, and yelk of dif- 
ferent eggs are very different. With the view of investi- 
gating this point, and of obtaining something like an average, 
the following experiments were made. The eggs were boiled 
hard in distilled water, and the different parts weighed im- 
mediately in their moist state. 
Shell and 
Membrane. 
Albumen. 
Yelk. 
Total. 
Grains. 
Grains. 
Grains. 
Grains. 
80 
394-3 
289 
763-3 
108 
593 
273-5 
974-5 
107.3 
375-8 
236.2 
919-3 
71-5 
5i6-5 
215 
803 
IO3 
503-7 
269.3 
876 
107 
515.3 
273-4 
895-7 
93- 2 
605.5 
252.4 
951-1 
927 
515-7 
2 57 
865.4 
96.8 
510.6 
210.8 
818.2 
77 -6 
567-4 
241.5 
886.5 
93-7 
529.8 
251.8 
8 75.3 
If we suppose each of these eggs to weigh one thousand 
* If the average of the above means be taken, the loss per day will be about .9 
grain. 
