millimetres. Inside diameter of cylinder 33 Stroke of piston 70 Length of cylinder inside 88 Length of piston 11 Clearance at each end 0.5 Diameter of piston rod 5 Length of cross-head 17.5 Diameter of guides 4.5 Distance from center to center of guides 26 Length of guides 110 Length of wrist-pin bearing 8.5 Length of connecting rod 150 Ratio of connecting rod to stroke 2-1/7 to 1 Length of crank pin 10 Diameter of main shaft 8 Length of main bearings 25 Distance from center of cylinder to center of valve stem 35 Length of valve 72 Width of ports 2 Outside lap of valve 4 Inside lap of valve 3 Lead of valve 0 Travel of valve 13 Cut-off from beginning of stroke 57 Exhaust opens End of stroke Exhaust closes on return stroke 48 Diameter of valve stem 4.5 Diameter of eccentric 36 Width of eccentric 4 Width of crank arm 4 The weights were nearly as follows: grammes. Engine 464 Pump and pump shafts 231 Gasoline tank and valves 178 Burners 360 Boilers, frames holding boilers, and mica covers over boilers 651 Separator, steam gauge and pipe for engine 540 Exhaust pipe 143 Smoke stack 342 In all, 2909 grammes, or 6.4 pounds. [Illustration: PL. 26A DIMENSIONED DRAWING OF BOILER COILS, BURNERS, PUMP, NEEDLE VALVE AND THRUST BEARING] [Illustration: PL. 26B DIMENSIONED DRAWING OF ENGINE NO. 5] [Illustration: PL. 27A SIDE AND END ELEVATIONS OF AERODROME NO. 5, MAY 11, 1896] [Illustration: PL. 27B AERODROME NO. 5 PLAN VIEW. OCTOBER 24, 1896] [p117]