380 
at each end of which there is an elliptical hole, which allows 
the screws to work easily (see Plate II.); while the screws 
bearing at top against the third beam, (which consists in a 
thin beam annexed to two upright ones) are kept steady by 
means of pivots.* The nuts being moveable and rounded 
underj by allowing the second beam to descend alternately 
nearly two fefrt more one way than the other, the work is in a 
great measure secured against the awkwardness and want of 
skill of the labourer. 
In the ordinary construction of this machine,- there is simply 
but one power in action ; instead of which, we have here three 
combined together. The first results from the base or lover 
beam, which raised from the ground and supported by blocks 
ot stone, and yielding to the pressure of the screws, re-acts 
upon the cheese. The second springs from the middle beam, 
which, being sawed in four planks, except sixteen inches in 
the middle, and thereby become very elastic, concentrates its 
force on the same point as the former. The third is derived 
from the upper beam, which, by adding essentially to the 
force displayed by the other two, consolidates the work, 
causes an opposition to the screws, and, by its redaction, pre¬ 
vents theirf heads from breaking. Such is the mechanism of 
ft press, thirteen feet and a half long, which I have had put 
tip, by means of which, six hogsheads of cider have often 
been pressed out in one day. A boy, with the help of a 
capstan, is able to work it. 
Formerly, when a screw broke, the accident never failed to 
occasion the loss of much valuable time ; but the means have 
been found to remedy it in a few hours. We are indebted for 
it to Sir John Dumaresq, chief magistrate of this island. 
At the most busy time of the season before last, the head of 
one of the screws broke, and rendered his press unserviceable j 
be called in workmen to no purpose, as they all declared that 
th'efe was nothing to be done besides substituting another 
screw ; he then contrived an expedient, of which the follow¬ 
ing is an abstract:—. 
He caused two spars to be brought, (see Plate III.) A A. 
from seven to eight inches square, and two feet longer than 
the screw ; he had them joined together in a parallel direction, 
about eight inches from each end, by two cross boards, BB. 
of four inches by six, sufficiently long to enable the spars, by 
embracing the lower beam at C, to allow the upper beam at D. 
to work up and down. 
* Timber may be used'for screws the very year it has been felled ; after 
boring a hole at the centre, from one to two inches in diameter, from one 
end to the other, it must be steeped quite green in water for some months, 
and then dried in the shade; this method prevents it fium warping; the 
screws are secured against vermin, and rendered perfectly smooth, by 
daubing them over with a mixture of soft soap and black lead in powder, in- 
the proportion of two parts of lead and one of soap. 
f Deal, being more elastic than other tiflabVj- * the most proper for the 
beams. 
He 
