64 SLIPPER GUIDE.

for the purpose of adjustment. The plan andside elevation of the arrangement undernotice is represented by Fig. 9—page 63. Thefollowing description will render the advan-tages to be duly appreciated:—

The cylinders are secured together oppositethe condensers, each pair being situated at theport and starboard sides of the keel of thehull. The slide valves are of the equilibriumtype, double ported, the packing at the backbeing of the ordinary kind, and a communi-cation from the condenser assists to reducethe face friction. The supply steam entersthe slide casing through that for the expan-sion valve, the latter casing being on the topof the former. Each casing is separatelysupplied with steam, so that an independentaction is preserved.

The link motion next claims attention. Inorder to preserve a direct action from theeccentric, the link—of the slotted kind—isarranged to rest on the block pin when thelink is lowered. With slide valves of maxi-mum area, two rods are introduced, each ofwhich are fixed by nuts to a crosshead; andbracket bushes, secured to the main frame,form guides, through which the slide rodspass. The link block pin is secured to thecrosshead centrally at the back, to retain acertain length of eccentric rod.

To correctly understand the arrangementof the gear for raising and lowering the link,a side elevation of it must be imagined.Below the link—centrally of the length of themain frames—is a weigh shaft. On thislatter is fixed a double lever; to which at oneextremity is hung a counter-balance, and theother is connected to a vertical rod. This

rod is attached at the upper end to a coarselypitched screwed rod, which passes through orfits in a bush supported in a standard, thelatter being secured on the slide valve casing.The bush in question forms part of a mitrepinion, which latter gears with another pinionfixed on the hand wheel shaft. Now, it canbe readily understood, that on motion beingimparted to the mitre gearing, the doublelever—by its connection with the screw—willbe raised and lowered. The connection ofthe lever with the link is by a rod, the latterbeing attached to the centre of the length ofthe link at the one end, and to the lever by aslot and pin at the other. By this connectionan almost equal action is imparted to the slidevalve, whether the link is raised or lowered.The position of the starting platform is be-tween the condensers, each engine havingseparate starting gear.

The hand wheels are situated directly overthe connecting rods, about midway of thelength of the guide channels; the othermanipulating gear being close at hand.

The main frames are designed with a properattention to the requirements of the same.The adjustment of the main brasses is attainedby caps—at the front,—bolts, and nuts. Itwill be noticed that the centre frame has adouble bearing, the central space being pro-vided for the spur wheel which imparts motionto the expansion valves. The crank shaft isin one forging, presenting little for furthercomment. The connecting rods are singlyconnected at each end with semi-solid headsand caps, adjusted by securing bolts and nuts;suitable oil cans and wipers for lubricationbeing correctly situated. The mode of guiding