The Composition of Milk produced on "English Bairij Fa/rms. 181 
and therefore best adapted to serve as a guide to the genuineness 
and purity of the milk. A great number of complete milk 
analyses have shown me that the three component parts con- 
stituting the non-fatty solids vary but little in the relative 
proportions in which they are present, parts of the non-fatty 
solids being milk-sugar, -^-^ part mineral matter (ash), and -^-^ 
parts proteids or nitrogenous matter, rather more than two- 
thirds of the latter consisting of casein, the specific component 
part of cheese. 
The first diagram, on pages 18G and 187, shows the average 
composition of all the milk received at the Company's premises at 
Bayswater. The number of farms from which the milk in question 
was supplied varied not only from year to year, but also during 
the different seasons. The results shown are means of analyses 
of morning and evening milkings. The most striking features 
which the curves indicate are the great uniformity of the non- 
fatty solids, and the rather large variations in the percentages 
of fat, which cause the total solids to fluctuate to about the 
same extent. Towards the end of the year, more particularly 
in November, the quality of the milk reaches its height, while 
in the spring months the poorest milk is received, another 
depression frequently occurring in July. 
The explanation is this : — In autumn the majority of cows are 
stale, and they then give a limited quantity of milk, which is of 
high quality. In spring most of the cows are newly calved, and 
the fresh grass, forming a very succulent food, causes an in- 
creased flow of milk of a poorer description. In summer the cows 
frequently suffer from either excessive heat, which burns up the 
pasture, or continuous rain ; and these unfavourable conditions 
are reflected in the production of milk, which becomes ijiferior 
both in quantity and quality. 
The same remarks apply to the succeeding diagrams, on pages 
188 to 201, which show the composition of milk received from 
several individual farms. Here a new item is introduced by giving 
the composition of the morning and evening meals separately. It 
will be seen that the evening milk is, with exceedingly rare ex- 
ceptions, richer in every respect than the morning milk. I have 
always been inclined to ascribe this difference to the account of 
the inequality of the intervals between the two milkings ; after 
the longer interval from P.M. to A.M. milking a larger yield of 
poorer milk being produced, and vice versa. The milking times 
are stated to be 5 a.m. and 4 p.m., and the proportions of 
morning to evening meal vary from 100 to 94 in the case 
of farm E, to 100 to 78 in the case of farm A. The chief 
time for the cows to calve is from November to May, with 
