This title I confess, seems very ambitious, as applied to an utensil for the dairy: but I had to express the combination of it’s own axis, and those of the leaves or wings about their respective axes, while gyrating round the common centre.
The principal shaft A B, [fig. 8 and 9] of [Plate 24], is the general centre of rotation; and a b are two lighter shafts carried round that centre, and turning at the same time on their own centres by means of the wheels e f geering in the fixed wheel c d, (of which one half only is drawn) and which forms part of the top of the churn. Each of the shafts a b, carries four leaves or wings (better seen in [fig. 9]) reaching from the top, nearly to the bottom of the vessel; and they run in proper steps in the cross piece m, and also in proper collars in the upper cross piece g h. In fine their wheels e f, and the fixed wheel c d, which turns them, are furnished with teeth on my patent principle; and therefore work without noise or commotion. Now, the principal shaft A B, rests on the step B at the bottom of the vessel; and runs, at top, in a collar formed in the metallic bridge i k, which, fixed to the outside rim of the cover, passes directly over the centre of the Machine. When therefore, the cream is put into the churn, (to do which the above mechanism is taken out) the mechanism is re-placed as now represented; and the main shaft set in motion by any convenient power: when the side shafts a b, turned by the fixed wheel c d, give a backward motion to the wings a b, and create a great agitation of the cream—for, it should be remarked, that this is not a circular motion: but each fly produces a kind of vortex round it’s own centre, while progressing round the common centre. The consequence of which, as above intimated, is, an unceasing agitation of the liquid, and, I believe, the best of churning. This however, I state as a mechanician, not having been initiated into the secrets of the dairy properly so called.
It may finally be observed, that the leaves or partitions l n, fixed to the sides of the churn, (beyond the reach of the moveable wings a b) are destined to prevent still further any general motion of the butyraceous matter; and thus to accelerate the churning process: and further these leaves, both fixed and moveable may be pierced with holes, like the analogous parts of other utensils of this nature.
OF
A HELICO-CENTRIFUGAL MACHINE,
For raising Water in great quantities.
The screw of Archimedes, is well known. When used to raise water it is placed obliquely, in such a position as that it’s hollow threads become more oblique to the horizon than the axis of the screw itself: observing which practice, some have said of this Machine, that it raises water by letting it run down: But this cannot be true. The threads of the screw merely wedge themselves under the water, and make it rise in a direction parallel to the axis of the screw; at the highest end of which it falls into the upper reservoir.
I once placed a screw of this kind upright, and said (in thought) is it then impossible to raise water by means of this screw thus placed? The answer in a few minutes was—“not at all; there is a force would make it easy: namely, the centrifugal force:” and this mental soliloquy was the origin of this Invention, which, some thirty years ago, I shewed to a public man, whom the lovers of the mechanical arts will long remember.