11^ INSTRUMENT FOR COUNTIKG THE LIFTS FROM A MiKt; 



Ihftrumcnt for and driven, or otherwife fattened, upon any gudgeon. I 

 mts"fiom^a* fuppofe the windlafslo be one yard in circumference; and 

 mine. • confequently forty revolutions of the windlafs are required 

 before the firft wheel B, upon which the brafs catch C is fixed, 

 turns once round. The pit, therefore, may be only ten yards, 

 or from feventy to feventy-five yards deep, yet it will make no 

 difference. All that is required to regulate the machine to the 

 depth of the pit, is as follows: — It' the pit be little more or 

 lefs than ten yards, the firfl wlied muft be fo placed in the end- 

 lefs fcrew, that the brafs catch C may be at the beginning, but 

 yud efcaped from the cogs of the fecond wheel D. It will 

 then only want five or fix revolutions of the windlafs backwards, 

 before the faid catch is ready to operate again. But fuppofing 

 the pit to be feventy yards deep, in this cafe, the catch G 

 imift be placed fo as nearly to be ready to a€t. By turjiing 

 ■backwards, the wheel may very nearly make two revolutions; 

 and as it can be ft ill turned as far (he other way, the catch will 

 only zQ. once, provided the faid wheel does not quite make 

 two revolutions. 



The model is about the fize required for a common hand 

 windlafs. The index will at orice (how how many times fifty 

 boxes, and how many above and below that number, have been 

 drawn up: not one of them can efcape. Allowance, however, 

 muft be made for the number of perfons who go op and down 

 in the fame way. Befides this, fince one box is always coming 

 up, whilft the other is going down, the numbers pointed at 

 muft be doubled, except a perfon was defirous to have a ma- 

 chine a6ling both ways, which would hardly be worth while. 

 As the machine is at preferU, though it points out a thoufand 

 boxes only, yet it will ferve for two thoufand. 



The fame mechanifm, with very little variation, may be 

 fixed to a horfe machine, called a gin, in this neighbourhood ; 

 viz. as a gin may be ten yards or more in circumference, the 

 a6lion would be too flow, if moved by an endlefs fcrew ; a 

 .pinion, with four leaves, will be found much more convenient. 

 This pinion is fixed to the end of the upper gudgeon, which en- 

 ters the box containing the machinery. As fome accuracy is 

 required to make fuch a pinion work well, and thefe machines 

 are often coatfely conftru6ied, it will be neceifary only to make" 

 about one inch and a half of the end of the faid gudgeon ex- 

 adly round, namely, that part of it which goes through the 



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