NO. 



LANTGLF/5 RIEMOIB ON MECHANICAL FLIGHT 237 



proved eminently successful in providing against future troubles from leaky 

 jackets. 



The general form of construction of the engine with the improved cylin- 

 ders will be readily understood from the drawings, Plates 78-81, in which Plate 

 78 is a detail sectional view, previously referred to, through one of the cylinders ; 

 Plate 79 is an end elevation of the port side, Plate 80 is a plan view, and Plate 

 81 is an elevation of the starboard bed plate which supports that side of the en- 

 gine, and by which it was fastened to the aerodrome frame, this view showing 

 particularly the sparking apparatus which was mounted on the bed plate. The 

 engine consists primarily of a single crank shaft provided with a single crank 

 pin, the shaft having bearings in a dram which consists essentially of two heads. 

 Arranged around the crank shaft and attached at equidistant points of the drum 

 are five cylinders. Mounted on the port side of the crank shaft and close to the 

 crank arm is a small gear, which through suitable gears mounted on the port 

 head of the drum drives a double-pointed cam which has a bearing on the ex- 

 terior of the hub of the drum. The ratio of these gears is such that the cam 

 is driven at one-quarter the speed of the crank shaft, and in the reverse di- 

 rection. Mounted on the exterior side of the port head of the dram are five 

 punch rods, the upper ends of which are within a sixty-fourth of an inch of be- 

 in- in contact with the exhaust- valve stems of the cylinders, and on the lower 

 end of these rods are hardened-steel rollers which rest on the double-pointed 

 cam — this one cam thus serving to operate the exhaust valves of all five of the 

 cylinders. The port head of the drum is connected to the port bed plate, by 

 which it is supported, by means of a flanged bushing in which are formed 

 tongues and grooves which fit into corresponding grooves and tongues formed 

 in the hub of the drum, it being necessary to have a certain amount of space be- 

 tween this bed plate and the head of the drum to provide room for the exhaust- 

 valve cam and its co-acting punch rods. The starboard bed plate is fastened 

 to the starboard head of the drum by bolts which draw the web of the bed plate 

 against the face of the drum. The sparking gears are driven by means of a 

 gear formed on a sleeve which telescopes over the hub of the starboard drum, 

 and has a bearing thereon, the end of the sleeve terminating in a ring which is 

 fastened to the crank shaft. 



Since the five connecting rods must center on the one crank pin, the bronze 

 shoes in which they terminate can occupy only a portion of the circumference 

 of the pin, and with the relative proportions which here existed between the 

 length of stroke of crank and the length of (lie connecting rod, the circumfer- 

 ential width of the connecting-rod shoes was slightly less than sixty decrees, 

 thus leaving uncovered a crank space of about one-sixth of the circumference, 

 which it was necessary to have in order to provide room for the change in rela- 

 tive position of the shoes due to the angularity of the connecting rods. In 



