240 The Trials of Milking Machines , 1913. 
force exerted by the vacuum. This seems to be a natural 
process very nearly imitating the action of the calf’s tongue 
and is undoubtedly of great benefit in keeping the teat in good 
condition and preventing numbness. 
The second of the two fundamental principles where 
external mechanical pressure alone is used, was found in three 
exhibits. This principle is more nearly akin to hand milking, 
and there was much ingenuity displayed in arriving at the 
necessary motions. In considering this type of machine from 
a bacteriological point of view it is at once apparent that 
without the very greatest difficulty there can be no provision 
made to prevent exposure of the milk to the air or contamin- 
ation from many sources. Reference to the bacteriological 
results of these trials will quite uphold this statement. 
Turning to the points to which the special attention of the 
Judges was called, as given on page 1, we will take a few of 
them and explain the construction which the Judges put upon 
them. Sub-sections (a), (6), (/), and perhaps (c), may all be 
summed up into what we shall call “ byre time.” In mentioning 
the term “speed of the whole proceeding” in milking a herd 
of cows, one must not forget that most of the best types of 
machines will strip fairly clean when left long enough to do 
so ; but that it is not an economy of time to do this. In 
practice it is found better and quicker to let the machine do 
the heavy work and to strip by hand. Say for instance that 
the machines can milk six cows at one time and that the 
machines have finished milking the first batch and are now 
started on the second, the one or more attendants will now 
proceed to hand strip the first batch, which they will certainly 
have completed by the time the machines are ready to be 
moved on to the third batch of cows. Another advantage in 
this method is that the massage incidental to hand milking is 
highly beneficial to the udder and teats. 
Sub-section ( d ). Security of attachment to teats is most 
important, and some of the machines were weak on this point. 
It can readily be understood that the chance of contamination - 
is very great where the teat cup or cups drop into the bedding 
in the byre with the vacuum still on from the main and the 
receptacle ready to catch all that the cups inhale. 
Sub-section (e). Gentleness in operation. Most of the 
machines had no difficulty in attaining this, and it has since 
been reported to us that the cows suffered no injurious effects 
from the trials. 
Sub-section (/). All the machines had simple means of 
regulating the speed of the pulsator. 
Sub-section {g). This point is dealt with fully in the 
bacteriological report. 
