A short Account of Horizontal Water- Wheels. 257 
livered from a spout, which is so directed as that they may be 
struck in a direction perpendicular to their surface. 
2. Those which have their floats ranged round the rim of the 
wheel in planes inclined to the radius, but parallel to the axis. 
3. Those which have the floats standing on a soal, or on the 
side of the rim, not pointing to the axis, but aside from it, so 
that they will admit of the spout being more conveniently placed. 
4. The centrifugal wheel, commonly called Barker’s mill. 
This consists of an upright pipe or trunk, communicating with 
two horizontal arms, each having a hole near the end opening 
in opposite directions, and at right angles to the arms. The 
water is poured from a spout into the top of the trunk, and 
issues through the holes in the arms, with a velocity correspond- 
ing to their depth helow the surface of the water, by which the 
arms are forced backwards, and a retrograde motion is given to 
the wheel. 
5. In the year 1797, a patent was taken out by Mr. Robert 
Beatson, for a method of constructing horizontal mills to go 
either by wind or water. The machine consists of four rect- 
angular frames or wings, standing at right angles to each other 
on an upright shaft. The floats, which consist of some thin light 
substance, are fixed in the frames perpendicular to the horizen, 
and are so constructed, that when they face the wind or the current 
of water, they are shut, and fill up the whole space within the 
frame; but on the opposite side, when they return against the 
current, they are open, and permit the wind or water to pass 
between them. 
This machine, as a water-mill, was intended to act in the cur- 
rent of a river, or by the ebbing and flowing of the tide. 
These seem to be the principal kinds of horizontal wheels; 
and from the nature of the principles upon which they act, it is 
evident their powers must be very small. 
It however appears that many are in use on the continent of 
Europe. 
An Explanation of the New Patent Horizontal Water-W heel, 
and the Principles of its Action. 
A cireular wall, in the form of a hollow cylinder, is built in a 
perpendicular position on a horizontal plane. 
Through the side of the cylinder, at the bottom, several rect- 
angular cuts or passages are made, the sides of which are per- 
pendicular to the base, or bottom of the cylinder, and the length 
of each within, is about four times the width. Fig. 1, Plate IV. 
The passages or cuts are made quite round the circumferences 
and so near to each other, that the sections of their sides within, 
make an acute angle, and leave, between each two, a solid part 
Vol. 50. No.234, Oct. 1817. R in 
