380 Dr. Prout’s experiments on the changes which take place 
grains, the weights of the constituent principles of each, when 
reduced to this common standard, will be as follow : 
Average 
Shell and 
Membrane. 
Albumen. 
Yelk. 
Grains. 
Grains. 
Grains. 
IO4.8 
516.6 
378.6 
110.8 
608.5 
28O.7 
116.7 
626.3 
257.0 
89.0 
643.2 
267.8 
117.6 
575 -o 
307-4 
119-5 
575-3 
305.2 
98.0 
636.6 
265.4 
107.1 
596-° 
296-9 
118.3 
624.0 
2 57-7 
875 
640.0 
272.5 
106.9 
604.2 
288.9 
Hence, if we suppose a recent egg to weigh one thousand 
parts, the relative proportions of the shell, albumen, and yelk, 
will be as 106.9, 604.2, and 288.9 ; and f° r the sake °f easier 
comparison in all the subsequent experiments, the numbers 
are reduced to the above standard, or to the supposition, that 
the original weights of the eggs employed were, when just 
laid, exactly 1000 grains. 
When an egg is boiled in water, it loses weight, par- 
ticularly if it be removed from the water when boiling, and 
be permitted to cool in the open air ;* the water also on exami- 
nation will be found to contain a portion of the saline contents 
of the egg. The loss of weight from boiling is by no means 
constant, but has been found to vary from 20 to 30 grains, on 
* When permitted to cool in water it sometimes gains a little in weight, owing 
to the absorption of water. Eggs placed in a strong solution of common salt are 
said to become highly saline throughout. This mode has been recommended for 
preserving them, but I have never tried the experiment. 
