504 The Trials of Grtam Separalo)'^ at Boncasiei'. 
separator, the machines being now called respectively, the 
" Leviathan," the " Alpha Baby," and the " Alpha Windsor." 
A series of separate thin sheet-steel discs placed one above 
another are interposed in the drum, being loosely arranged 
around the spindle on which they are, so to say, threaded, and 
are kept about of an inch apart from each other by means 
of projections stamped on them. In the " Alpha Baby " machine 
there are twenty-six discs, each measuring 2^ inches across the 
top opening, and 4 inches across the bottom; the "Alpha 
Windsor " has twenty-seven similar discs, but in the " Levia- 
than " there are fifty-six, and of larger size, these measuring 
2f inches across the top opening nnd 9 inches across the bottom. 
A sketch of a single disc is here given. By 
the interposition of the discs the milk is 
divided up into thin layers, and, each disc 
acting itself as a miniature separator, the 
separation is much more rapidly effected, 
for, as demonstrated at the trial, the result 
" At^h^?iScrine"'aiuMn IS practically to double the outturn. This 
the " Leviathau." yyas the case in all three of the machines 
to which the arrangement was attached. 
Against this must be set the extra time and trouble required in 
cleaning and re-adjusting the discs after each time of working, 
and, of course, also the extra cost. 
The trials commenced on Wednesday, June 17, and occupied 
this and the three following days. The points to which the 
attention of the Judges was specially directed were the 
following : — 
1. Price. 
i'. Power talien per gallon. 
3. Efficiency of separation. 
4. Means of regulating' thickness of cream, 
5. Facility for dismantling and cleaning. 
(5. Mechanical construction. 
7. Freedom from froth, both of skim-milk and cream. 
In Table I. (page 50G) are given the respective prices, power 
employed, number of revolutions, &c. ; while in Table II. (page 
507) the particulars of the sejmration and its efficiency are stated. 
The machines were all driven for testing by means of an 
electric motor, actuated by a dynamo driven by a balanced 
engine as ordinarily made by the Society's Engineers, the power 
being ascertained by the quantity of current used. This was 
read off by Mr. Prentice, one of the engineering assistants, by 
means of delicate instruments. So delicate was this test that, 
upon one of the exhibitors ajiplying a pocket revolution indi- 
