The Evolution of Agricultural Implements. 249 
In reply to this appeal, the mechanic says that a system under 
which each dairy-farmer converts his own small quantity of milk, 
whether into butter or cheese, is a wasteful one, and recommends 
that the raw material be sent to some central factory, where, 
large quantities of milk being treated together, manual labour 
could be displaced by machinery, while the quality of the pro- 
ducts would be improved. 
Such factories, or “ creameries,” as they are called in America, 
where they are universal, are now being tentatively introduced 
into England, the most important of these establishments being 
the Duke of Westminster’s Aldford Cheese Factory, Lord Vernon’s 
Sudbury Creamery, the Dunragit Creamery Company, and the 
Berkeley Vale Shorthorn Dairy Company. Briefly to describe a 
“creamery,” whether American or English, will be to exhibit in 
as much detail as is here admissible the aids which, up to the 
present time, have been placed at the service of the dairyman 
by the agricultural engineer. 
Milk, on arriving at the butter factory, is first weighed in 
specially contrived scales, whence it is tipped into a neighbouring 
tank. No milk is received unless of a given specific gravity, or 
at a higher temperature than 80° F. From the tank, the milk 
flows into the “ cream separator,” a device which was first applied 
to the separation of cream from milk by Laval aboutl879. Laval’s 
separator consists of a cylinder rotating at a speed of six or seven 
thousand turns per minute. Whole milk, admitted to this whirl- 
ing vessel, parts with its cream in the following way. The heavy 
milk is thrown outwards to the circumference of the separator, 
while the lighter cream remains, floating upon the milk nearer 
the centre of the centrifuge, each liquid being withdrawn from 
its respective zone through suitable pipes. 
Laval’s separator having proved a great improvement on the 
old plan of “ setting,” has given birth to a number of other 
machines having similar functions, all of which must, however, 
be considered as modifications of a centrifuge, patented by 
Weston of Boston, U.S.A., in 1867, for the purpose of “ sepa- 
rating liquids from paint and other solid substances.” 
From the separator, the cream passes into the churn, an 
instrument protean in form, but needing no description. When 
the butter has “ come,” it is removed by wooden scoops and 
transferred to the “ butter-worker.” This machine, to which 
the French and Dutch dairymen owe much of their success in 
supplying the English market with a uniform sample of butter, 
is an extremely simple contrivance. In its best-known form, it 
consists of a revolving table, sloping slightly from the centre to 
the circumference, upon which the butter is squeezed under a 
