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MINUTES OF PKOCEEDINGS OF 
Triangle Gyn . 
Diameter of square of windlass = 0' 9". 
„ barrel ,, = O' 8". 
Length of socket = 0' 11|"» 
Length of lever = 7' 1". 
Depth of lever in socket = 0' 7". 
Distance of rope from end of lever = 0' 5". 
.*. effective length of lever = 7' 4|". 
The diameter of the fall may be taken as = 1". 
P : W :: 1 : 98*33. 
Gibraltar Gyn . 
The Gibraltar gyn which is used for mounting and dismounting ordnance 
on, or from standing carriages, in situations where it would not be convenient 
to use the triangle gyn, possesses the following mechanical powers com¬ 
bined in it, viz. 
A compound wheel and axle. 
A tackle, consisting of two triple blocks. 
Eadius of circle described by Handle of windlass=13". 
Eadius of windlass = 3". 
The fall is 3|-in. rope. 
The large wheel has 57 cogs. 
The small do has 11 do. 
Assuming diameter of rope as 1 in. 
.-. P : W :: 1 : 115*4; ' 
of which a very considerable amount is lost by friction, &c. 
Sling Wagon . 
Diameter of square of windlass = O' 9". 
,, barrel „ = 0' 8". 
Length of socket = 0' 114". 
Length of lever = 7' 1". 
Depth of lever in socket = 0' 7". 
Distance of rope from end of lever = 0' 5". 
Effective length of lever = 7' 4J". 
Taking the diameter of sling as 2 inches. 
/. P : W :: 1 : 35*4. 
