Report on the " Working Dairy" at the Derhy Show. 641 
and appparancc, and though it is said to be capable of separating 
100 gallons of milk an hour, it requires more power and is three 
times as costly. 
The top of the Lefeldt being lifted off, it displays a domed 
kind of inner case, with a central hole through which the milk 
is conveyed to the bottom of the centrifuge. The cream is 
thrown over this dome top, between it and the outward case, and 
passes by a deep groove all round through the spout by which it 
escapes. 
The difficulty of working this machine was illustrated in one 
of its runs, 5.20 P.M. on Wednesday. After a few minutes it 
was found that the cream-spout was blocked. After the machine 
had been brought to a stand and the top removed, the internal 
cylinder or feeder had to be taken out before the tube could be 
examined. In justice to this machine, it must be observed that 
the work it made seemed admirable. 
I now come to the chief novelty in this department, the new 
Danish Separator, to which I have before alluded. This instru- 
ment is very different in appearance from its companions, the 
Laval and the Lefeldt. The same principle is adopted, but the re- 
volving cylinder is open at the top, and consequently the actual 
process of separation can be observed. The milk is put into a 
wooden barrel-made vessel, elevated above the separator, from 
Avhich it flows by an easily regulated tap into the revolving 
vessel. It is immediately thrown by the centrifugal action of 
the revolver into a vertical wall round the sides of the cylinder ; 
and two brass tubes, sliding in slots on the upper rim of the 
outer case of the machine, and easily regulated to tap, so to 
speak, one the external body of milk and the other the internal 
wall of cream, convey the separated products to their respective 
receptacles, the same centrifugal action which separates the milk 
and cream forcing them through the small orifices of their 
respective tubes. 
The action of the machine, as well as its general appearance, 
will best be explained by the accompanying illustrations. 
" The diameter of the drum inside is 25 J inches, so that the 
internal circumference will be about feet ; and as the number 
of revolutions are 1500 a minute, 6^ X 1500 = 9750 as the 
surface speed, the measure of the centrifugal force required by 
the Danish separator to separate the cream from the milk, which 
is 5250 feet less than the Laval machine."* The advantages of 
this instrument over its rivals certainly seem to be great. In 
addition to its open action so that the whole of its operation is 
manifest, and its moderate speed, which I have before mentioned. 
' Derby Mercury,' July 20. 
