An ordinary class of slide-rods are those having long screws at their outer ends. These ends are connected to their respective crossheads by means of nuts, the slide-rod screws being in the crosshead bosses, and nuts on the boss-faces. An arrangement of this class is show by Fig. 971. The diameter of the hole in the boss is sufficient to allow the screw to slide easily to and fro, so that it can be put at any desired distance through the boss, and be tightly fastened in that particular place by screwing the nuts forcibly against the boss-faces. A connexion of this character is very convenient for adjusting the slide-valve to any desired place on the cylinder-faces; and the adjustment can be performed without trouble either at the first attachment of the valve, or at any future time when repairs are in progress.

In order that the ordinary to-and-fro motion of a slide-rod may not loosen its nuts, and thereby allow the valve's relative situation to be unintentionally altered, the rod's end should be screwed with a thread of comparative short step, and made to tightly fit the nuts. In some cases, four nuts are used for each rod, instead of only two, two nuts being situate at each end of the crosshead-boss.