302 Hydraulics for Farmers. [June, 



" I have as yet," says Mr. Strode, " made only three different 

 sized macliines, excepting the model which I left in the Patent- 

 office, which is of glass, and a brass one of the same size, which 

 is now in the Franklin Institute, Philadelphia. The latter is an 

 operating model: its linear dimensions have a ratio to this cut, 

 Fig. 6, of about 32 to 7. This model, under a head of 5| feet, 

 with a driving pipe about 15 feet long, ^ inch calibre, forced 

 through a \ inch pipe 1.8 lbs. of water 40 feet high, in one 

 minute, which is about 324 gallons, or lOj barrels in 24 hours. 

 The three sizes above mentioned have a ratio to the aforesaid 

 model of 3, 2| and 2, in their linear dimensions. The largest of 

 these is calculated to work with a 2 inch driving pipe, but will 

 work very well with \\ inch, lliese machines will work under 

 all heads, where they have yet been tried, with driving pipes of 

 various lengths. I have not yet made a sufficient number of ex- 

 periments to determine what the length of driving pipes of given 

 calibre, under a given head, to force water to a given elevation, 

 should be so as to produce a maximum per centage, nor what the 

 length should be to force up a maximum amount, without regard 

 to per centage; but I am well satisfied that they do not exist con- 

 temporaneously. The quantity of water used, and of that forced 

 up, may be varied by giving the outlet valve a longer or shorter 

 stroke, by which the number of strokes in a given time is dimin- 

 ished or increased; and in each individual case there will be found 

 to be a certain number of strokes, that will cause the machine to 

 raise the most water of which it is capable, without regard to the 

 quantity it uses to produce this effect; but when it is desirable 

 that the quantity of water used shall raise the most water possi- 

 ble, then the number of strokes must be regulated to produce this 

 effect." 



"I give you one solitary experiment that was made with my 

 largest machine, to produce the former of these effects. It worked 

 under a head of 12 feet; the driving pipe was 1| inch calibre, 40 

 feet long. By using 135 pounds of water per minute, 20 pounds, 

 (which is 114' barrels in 24 hours,) were forced through a | inch 

 pipe 60 feet high, in the same lime. The machine during this 

 time made about 32 strokes, which was the right number, with 

 this length of driving pipe and the attending dircumstances, to 

 force up the most water, without economising the water used. It 

 is altogether likely, as the length of this pipe was taken at hazard, 

 that some other length, in the same situation, would have forced 

 up more in its maximum operation. You will perceive that the 

 above experiment gives for the machine a little above 74 per cent. 

 By increasing the number of strokes to 40, about 75 per cent was 

 obtained; but the quantity raised was diminished a little, and the 

 quantity used was diminished in a little greater ratio." 



