longitudinal section

The above was a longitudinal section, but now let’s look at a cross section.

A longitudinal section of the tapering tube end, with the screw-thread as actually formed, is shown full size in Fig. 291a for a nominal 21⁄2 inch tube, that is, a tube of about 21⁄2 inches internal diameter, and 27⁄8 inches actual external diameter.

A longitudinal section through the centre of the machine is shown in Fig.

Fig. 3390a is a longitudinal section through the boiler and one steam cylinder and pump.

It will be seen in the longitudinal section, Fig. 3390a, that the steam valve face is a segment of a circle and therefore answers, so far as the distribution of the steam is concerned, to a simple D slide valve, which exhausts through the pipes m, p.