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THE CIVIL ENGINEER AND ARCHITECTS JOURNAL. 



120 



iipcted to tlie body of the caniage by means of springs, and kept in their 

 places by guide plates, so that it is only necessary for the tondoncc to move 

 in a curve to exert a force sufficient to alter the position of each journal, 

 ■^'^y-i^:^-^ of an inch, in oriler to pass round a curve a mile radius 

 solely by the influence of the cone, a quantity so small that the Doctor 

 will find great difficulty in |)ersuading practical men that it is " impoi- 

 stblt" such a deviation can take place, more especially as we see a 

 force equal to TOUlbs e,ndeavou.iiug to produce it. 



In'^uiker. 



VERTICAL WATER-WHEEL. 



Fig. 1. — Elevation. 



The accompanying engravings represent a vertical water-wheel, 

 upon the principle of Barker's mill, which I erected at the iron- 

 works of the United Mexican Mining Association at Durango, in 

 Mexico, in 1832, for the purpose of driving a circular saw ; it was 

 desirable to produce a rapid movement witliout the intervention of 

 gearing, and this not being possible by means of the breast wheel, 

 which was, besides, fully loaded with the blast machinery, it occurred 



to me to avail myself of Barker's mill ; I first formed a rough working 

 model, upon the usual construction, but found the action of it so very 

 feeble, that I surrounded the arms with boards, in order that the 

 flowing water might impinge against them; this arrangement quad- 

 rupled the velocity of (he machine : I then added the upper part, 

 which was a still further improvement. The height of fall was about 

 S feet, the bore of the pipe about 12 inches, the length of the legs 

 about 30 inches from the centre, tlie size of the orifices about 0x2=: 

 12 square inches, the velocity 4U revolutions a minute ; by the period 

 it was completed and set to work, the works were suspended, so that 

 nothing further was done with it; I had an ulterior object in view in 

 constructing this machine, viz. to devise some simple and efficient 

 means of working the "tahonas," or grinding mills used in the reducf- 

 tion of the silver ore in the mining districts; this wheel would have 

 been in these cases invaluable, as it was formed entirely of timber, 

 excepting the step or shaft, and tlie few bolts and hoops with which 

 the tube and legs were bound together; it would never have got out 

 of order, and could not have been broken by any, but a wilhd accident ; 

 any country carpenter could make it. and keep it going, and it required 

 noheavy or large timber in its construction, for it can be supported 

 as well by a wall, as the timber framing shown in the drawing. 



Figure 1 is an elevation, the wheel and water-course shown in sec- 

 tion. Fig. 2, a plan of the upper wfieel, and Fig. 3, a plan partly 

 shown in section of the legs and tube. 



The same letters refer to each figure, so far as the parts are shown 

 in each. A is the vertical pipe, mounted on the box B, forming the 

 legs, the water issues from each extremity, and im}iinges with great 

 force against the fixed floats ;(, ii, &c., of the fixed tub c, and ulti- 

 mately escapes through the holes o cut in the bottom of the tub. 

 Upon the upper end of the pipe a cross frame is fixed, which carries 

 the horizontal or upper wheel, which has furnished all round its in- 



Fig. 2.— Plan of Upper 'Wheel. 



Fig. 3.— Plan partly shoHn in section. 



terior circumference vertical float-boards )•, and horizontal floats n, 

 which form cells, the water escaping into the tube through radiating 

 openings left in the bottom as shown, thus advantage is taken of the 

 momentum of the water rushing into the wheel. E is the vertical 

 shaft, upon which the crown wheel G is hung, working the pinion L, 

 which conveys the motion of the wheel, through the medium of its 

 shaft, to the mill ; J is the water and water channel, I the sUdce, K 

 the pinion to lift the sluice, H the framing by which the wdieel is 

 supported ; the movement of the wheel is in the direction of the 

 arrows shown in Fig. 2, and the reverse of those shown in Fig. 3. 



15, Stamford Stmt. 



W. J. CURTIS. 



