488 Deerfoot Farm Centrifugal Dairy. 
Another analysis, this last by S. P. Sharpies, October 22, 
1880, of the milk of the preceding day, gave : — 
Constituents. 
Water .. 
Fat 
Casein, &c. 
Sugar . . 
Ash . . 
87-94 
2-23 
4-24 
4-85 
0-74 
Slvim-inilk. 
90-47 
0-07 
4-03 
4-70 
0-77 
The specific gravity of the cream at about this time, as pre- 
pared for market, was determined by me as 1014. A sample 
taken from the machine, ran purposely for a considerably longer 
time, gave a specific gravity of 962 ; more recent results give 
even less, 956-4, the cream being longer under the influence of 
the machine. 
It is of interest to note that all the heavier impurities in milk, 
under the influence of the centrifugal force, seek the circum- 
ference. Here collects, after a time, a slimy layer, greenish in 
colour, largely miscible in water, and extremely offensive. The 
microscope develops granules, epithelial cells, and various con- 
stituents of dust. A sample analysed by Lawrie and Terry 
gave : — 
Water 67-38 
Fat 3-25 
Casein, &c 25-49 
Ash 3-88 
October 21, 1880, I was on hand early in the morning, and 
superintended an experiment with the larger machine. The 
process was carried on by the man in charge in the usual 
course, except that the machine was run from 7.45 A.M. to 
8.25 A.M. before the cream was commenced to be removed, a 
rather longer time than usual, or forty minutes. The last of the 
skim-milk was removed by 8.42 A.M., this intervening time 
being caused by the addition of a quantity of skim-milk after 
the removal of the cream by the pipe-scoop, after each succes- 
sive withdrawal of cream, in order to bring the cream surface 
over the horizontal diaphragm, which has no obvious object or 
use as connected with the theory or working. The analysis 
of the milk, as collected in a bottle from the pipe leading 
into the machine from the delivery tank, was found by S. P. 
Sharpies to be : — 
