
70 REPORT OF THE First ASSISTANT OF THE 
: of soluble salts, potash and soda (in larger part as chlorides), 
phosphoric acid, carbonic acid, lime, silica, magnesia, iron and 
sulphur. 
The shells consist largely of carbonate of lime, with some 
phosphates and organic matter. 
Analyses by Vauquelin and by Proust gave: 
v. P. 
Per cent. Per cent. 
OUT GOMREG OF CALCIIINY 0115.5! 00 aly nh bata elttuelsip's holy Lem Rane 89.6 91.0 
Phosphate of calcium and less phosphate of magnesia. 5.7 7.0 
Animal matter containing sulphur.................. AE ey eae 0 
Analyses of egg shells by W. Wicke gave: 
Goose. Hen. Duck. 
MICAMIT CAT DON AGE Wh) Jide). goists Uiavslay Wynn ion 95.26 93.70 94.42 
Magnesium carbonate ................-. 72 oe .50 
Agia [a nC a SRR OR SU a ga eR AT 76 84 
VeCer eT SU DSEANCER! 1.1) 600 4 Vise weil e aie epee 6 3.55 4.15 4.24 


Roussin found when different mineral salts were added to the 
food of hens, that the calcium carbonate of the shells was more 
or less replaced by isomorphous salts, “carbonates of barium, 
strontium and even of lead, but especially by magnesium carbon- 
ate.” “The addition of calcium arsenate was fatal to some of the 
hens, nevertheless arsenic was found in the egg shells.” ‘“ When 
alkaline bromides and iodides were added to the food, alkaline 
chlorides of the white and yolk of the egg were partly replaced 
by these salts. The increase in the proportion of bromide or 
iodide was, however, attended with a diminution of the calcareous 
envelope, which untimately disappeared altogether, leaving the 
ege surrounded only by a membrane.” It is not at all probable 
that the small quantities of bromide which are given to hens in 
medicine have any injurious effect on the egg. 
Eggs (of different breeds) which we have had for hatching 
averaged a greater weight than those laid by the pullets, in the 
experiments reported. The average weight per egg was 2.07 
ounces. The Brahma eggs were the largest, averaging 2.32 
ounces. The average of Light Brahma, Plymouth Rock and 
Buff Cochin eggs was 2.14 ounces; White Leghorn eges averaged — 
2.09 ounces. Other white-shell eges averaged considerably less. 

