1921.J 
Birks.—Electric Power for Milking-plants. 
113 
with before 8 a.m. and not being required again until about 5 p.m. Such 
load, therefore, allows an undertaking to work on a higher diversity-factor, 
produces a better load-factor, and tends to flatten out the daily load-curve, 
at the same time yielding a substantial revenue. 
■ Additional important advantages are available from the supply of 
electric power in the milking-shed. Once the mains are run for driving 
the milking-machine the power can be used for heating water during the 
intervals when the milking-machine is shut down. One horse-power of 
energy is capable of heating up 12 gallons of water from 50° F. to the 
boiling-point in nine hours. This is sufficient to scald out thoroughly the 
whole of the milking and separating plant. The apparatus is very simple 
indeed, consisting only of a 10-gallon cistern with the small electric-heating 
element brazed into the bottom, and provided with a change-over switch 
which automatically connects up the heating-element when the motor is 
stopped and disconnects it when the motor starts up again. At a small 
additional charge another such cistern might be fitted in the kitchen, and 
another in the bathroom. These cisterns must, of course, be thoroughly 
and carefully lagged with a good heat-insulating material, such as felt, 
pumice, or asbestos composition, in order to prevent the loss of heat by 
radiation during the long period of heating if the above efficiency is to be 
attained. As compared with the usual method of scalding by carrying 
across a couple of kerosene-tins of fairly hot water from the kitchen— 
probably several chains away—spilling and cooling it on the way, until 
there arrives at the milking-shed some 6 gallons of only fairly hot water, 
the innovation of 12 gallons of electrically-heated boiling water right on 
the spot may work a revolution in dairying second only to that due to the 
introduction of the milking-machine itself. Owing to the reduction in the 
labour of milking, the milking-machine has resulted in the large quantity 
of butter-fat now produced in New Zealand. Owing to the improved clean¬ 
liness of the apparatus, the electric hot-water system may yet have as 
important an influence on its quality, and with the increasing amount of 
milk that is going into preserved- and dried-milk processes the high quality 
is of increasing importance. 
The most effective application of electric power to the milking-machine 
work under New Zealand conditions will consist of a small self-contained 
outfit consisting of the electric motor, a vacuum-pump, a cream-separator, 
a small water-supply pump, and a 10-gallon hot-water cistern with the 
necessary switch-gear, all mounted on a compact hardwood base-plate, so 
that the outfit can be carried out, put down on the ground with no prepara¬ 
tion at all, connected up, and put into service straight away. Such units 
are required not by the hundred but by the thousand in the dairying 
districts of New Zealand. When they are thus standardized the distributing 
authority should stock them in quantity, so that they can be put in the 
back of a Ford car, run out, and put into service at a couple of hours' 
notice. 
The tests referred to in this article were carried out by Mr. H. E. Phil- 
pott, Electrical Tester, of the Lake Coleridge Electric Power Department’s 
staff, and will be continued as occasion offers. 
8—Science. 
