186 
POPULAR SCIENCE REVIEW. 
schools, charities, and all institutions in which large 
quantities of milk are annually consumed. 
A few years ago I made some accurate gravity determina- 
tions of pure milk before and after skimming, and of samples 
mixed purposely with 10 to 50 per cent, of water, and as the 
results may be useful in comparing them with others, I 
have incorporated them in the subjoined table : — 
Specific Gravity 
Specific Gravity 
at 62 ° F. 
at 62 ° F. 
before Skimming. 
after Skimming. 
Pure milk 
1*0314 
1*0337 
„ „ + 10 per cent, of water 
1*0295 
1*0308 
» „ + 20 
33 
1*0257 
1*0265 
?> „ + 30 
33 
33 
1*0233 
1*0248 
» » + 40 
33 
1*0190 
1*0208 
33 v> + 50 
33 
3 
1*0163 
1*0175 
In illustrating the utililty of these lactometers I may give 
several complete analyses of London milk and partial deter- 
minations which I recently made. 
The samples from the Strand district were all obtained from 
retail dealers in different courts and poor quarters in that 
locality. 
Those from Camden Town from respectable shops, and 
those from Kensington from shops and dealers who principally 
supply the wealthier inhabitants of the parish. 
Composition oe Five Samples op Milk. — Strand District. 
Water 
1 
2 
3 
4 
5 
93*75 
1*72 
1*75 
2*13 
*65 
93*04 
2*25 
1*75 
2*57 
*39 
90*98 
2*58 
2*50 
3*41 
*53 
93*32 
1*69 
1*69 
2*64 
*66 
88*38 
3*84 
3*18 
3*90 
*70 
Pure fatty matter 
*Caseine (curd and a little albumen) 
Milk-suo-ar 
Mineral matter (ash) 
^Containing nitrogen 
100*00 
100*00 
100*00 
100*00 
100*00 
*28 
4 
1*019 
1*020 
*28 
6^ 
1*017 
1*019 
*40 
6 
1*021 
1*023 
*27 
4i 
1*020 
( Not c 
\ mil 
*51 
12 
1*030 
eter- 
led. 
Per-centage of cream by volume 
Specific gravity of milk at 62°.., 
Specific gravity of skimmed ) 
milk at 62° F ) 
Partial Analyses and Determinations in some Samples op 
Milk. — Strand District. 
Spooifin Gravity of milk 
0 
7 
8 
9 
1*018 
5 i 
1*022 
7 
1*021 
6 
1*021 
5 
Percentage of cream by volume 
