TRANSACTIONS OF SECTION M. 733 
variation in churnability, due to the fat-globules, each cream must be considered 
as being obtained, not from milk of any particular breed, but from milk of a 
particular mean-sized globule. 
Before this could be determined it was necessary to ascertain the optimum 
temperature for churning, and to determine the amount of loss in churning at 
various temperatures. 
In the work now published the optimum temperature was ascertained and 
found to be 52° F. for all creams; that is to say, the lower the temperature the 
less fat is left in the butter-milk. 
With sweet cream, as much as 30 per cent. of the total fat may be lost in the 
butter-milk if too high a temperature is used. With ripened cream, as much as 
20 per cent. may be lost. Curves are drawn showing the loss due to too high a 
temperature. ° 
A series of analyses of the nitrogen-containing constituents was given, with 
photomicrographs and measurements of the globules of the milks. No correla- 
tion between any of these constituents and fat-globules could be ascertained. 
The question of a membrane surrounding the fat-globule was considered, and 
an attempt to repeat Storch’s work discussed. An artificial milk was prepared, 
all the constituents being ‘membraneless.’ A film of this milk, dried and 
stained, showed the same characters under the microscope as an ordinary pure 
milk. So it is considered that Storch’s membrane does not exist, but that the 
colloids in milk are absorbed by the fat-globules so as to give rise to a resem- 
blance of a.membrane. Storch’s analytical figures were explained on this 
assumption. 2 
Figures were given proving that the presence of large fat-globules in a milk 
enables more of the smaller ones to be separated in a mechanical separator. 
Results of experiments were given, in which foods of varying ‘ratios’ were 
given to cows, to determine their effect upon the size of fat-globules. 
5. The Oat Kernel. By Professor R. A. Berry, F.I.C. 
A summary of the more important results obtained from an extensive series 
of analyses of the oat kernel extending over several years, and now numbering 
over seven hundred complete analyses, was given. The oats were grown at the 
experiment station of the West of Scotland Agricultural College, on various 
farms in the West of Scotland, and, in addition, in 1911 at a few centres in the 
South of England and Wales. 
The results are best considered under the following headings :— 
Variety.—By tabulating the grain of over a hundred varieties, according to 
the percentage and weight of kernel, along with the chemical analyses it is 
possible to distinguish several more or less well-defined types : Zhe White Grains 
group into: (1) Small grains with a thin husk, a high percentage of oil, and an 
average percentage of nitrogen. These are characteristic of and include the old 
Scotch varieties with the newer selected strains from same. (2) Large grains fall 
into two groups : (a) A thick husk, a low percentage of oil, and high nitrogen ; 
(b) a thin husk, a higher percentage of oil, and a lower nitrogen. (3) Grains inter- 
mediate in character and chemical composition to the large and small include 
the bulk of the newer hybrid varieties. Zhe Black Grains grade into (1) small 
grains with a thick husk, low oil, and average nitrogen. (2) Medium grains 
with a thick husk, high oil, and low nitrogen. (3) Large grains with a thin husk 
and the richest kernel of the cultivated oats. These are the winter oats. The 
reddish and yellow grains form separate groups. The wild oat surpasses all in 
richness of kernel. 
Variation of the Kernel.—In this respect the results show that climate is 
the most disturbing factor. Distinguishing characters associated with a certain 
set of climatic conditions become greatly modified and, in some cases, almost 
obliterated when the conditions are radically changed. Scotch seed sown in the 
South of England and Wales in the warm and dry summer of 1911 yielded grain 
of a smaller and drier kernel, a thicker husk, higher nitrogen, and lower oil and 
weight per bushel than grain grown in Scotland. The cooler and more humid 
climate of the West of Scotland and the longer maturation period produce in 
