144 MACHME FOR SAVING PERSONS 



The wheels are low and ftrong, placed near the cor- 

 ners of the bafe. They have locks, to be ufed when the 

 machine is loading. 



The bafltet is breaft-high, and wide enough for four 

 perfons. The three iron rods keep it more fteady than 

 cords would ; and their openings admit one perion at a 

 time. It hangs free from the end of the lever. 



The principles of this conftru£lion arife from the re- 

 quifite properties of this machine : It mull be fpeedily 

 brought ; readily fitted ; prarticable in confined places ; 

 want no fupport from the wall ; reach a conliderable height, 

 and alfo project over obftacles on or above the ground ; 

 take down feveral perfons at once, and without any 

 exertion of theirs. The two vertical pieces folded, with 

 the lever oblique, can both be houfed and eafily carried : 

 when put in adiion, they expand gradually ; and the 

 lever is high when at full length. The bafe may be con- 

 venient, becaufe its own weight, with the trunk and the 

 four men at the windlafles keep the centre of gravity 

 pretty low ; and all the prefTures bear perpendicular on 

 the longer face. Befides, people may fit down on the 

 fides, or hold it by handfpikes, which may be kept on 

 it, and when wanted, put into holes near the margins, fo 

 as to projedt outwards.* A level pofition being very ne- 

 ceflary, a plumb rule fhould alfo be hung on the trunk. 



The cylindrical form of the fhaft and focket pro- 

 cures an eafy gliding motion, that lefTens the occafional 

 fideway bearings. It is alfo lefs alterable by wear, and 

 change of weather ; it makes the fliaft more folid, and 

 thus requires lefs bulk in both pieces. The two quarters 

 of the trunk which are flit for a communication of the 

 ropes with the fhaft, will yet be ftrong enough by the 

 folid piers that bear the pulleys. The other two have 



* It is wider on the model th^n it appear? under an oblique perfpeftive. 



fufficient 



