shaft, and has no timing valve, and, unlike the general practice of this firm, is not provided with a renewable liner to the cylinder.

All the engines previously described have been of the horizontal type, but as there are many positions where, from considerations of room, it would be impossible to fix a horizontal

G

FIG. 15.--3 H.P. NOM. VERTICAL CROSSLEY ENGINE (SECTIONAL PLAN)

engine, it has been found necessary to make a vertical one, and figs. 14, 15, and 16 show in section, plan, and external elevation such an engine of 3 H.P. NOM. The cylinder being 7 inches diameter by 10 inches stroke, is formed by forcing a liner A, by means of a gland B, into the main casting C, and leaving an annular space between the two to form a water jacket. The

joints are made at the bottom by asbestos to withstand the heat, and at the top by a rolling rubber ring D. In all respects this is an almost ideal engine of a vertical pattern.

The valve arrangement is simplicity itself. The box E, which is easily disconnected, contains the gas, air, and exhaust valve. The gas valve F is connected by the passage G to the gas cock shown in the elevation. The air valve H and exhaust valve I, whilst having the same passage, J, to the cylinder, have separate passages in the box E. The air is drawn through the silencer K, and the exhaust outlet is shown at L.

The Clerk-Lanchester pressure starter is used by these makers, and fitted to all large-sized engines.

4.75

G.5

9.8

13.

15.6

3.5

7.8

10.5

11

10 9 7

14

636660EGGGA30036

2

5

c. q.
10 0

2 150 0

144 O

210 O

10

220 0

699699699127 55555777

41

200

12

8

10

10

111

11

21

13

21

14

21

160 16 21

160 17 24

7 22 101 160

3341

11002

2 11

3

4

in. in.

to

300

200

200

200

9

200

101 23

HIGH-SPEED ELECTRIC LIGHT ENGINES (SINGLE CYLINDER)

6

It is interesting to note that the 1879 catalogue from which the foregoing table is taken contains the following: Tenders for larger sizes and for "compound engines" on application.'

Robey & Co. (Limited), Lincoln

On the expiration of the Otto' patent Messrs. Robey & Co. decided to manufacture gas engines, using the 'Otto' cycle, with various structural modifications introduced by the author in 1890.

Figs. 17, 18, and 19 being a section, plan, and external elevation of an engine capable of developing 24 B.H.P., represent the characteristic features of the valve arrangements of all sizes. The cylinder of this engine is 11 inches diameter and the stroke 18 inches. It will be seen that the cylinder A and bed are in one casting, the water jacket B coming well up to the end of the liner C, which is forced in from the back, and made tight by metallic joints only, and kept in position by the combustion chamber F, which is bolted to the end of the cylinder, having a projection fitting into a recess formed by making the liner a little shorter than the cylinder. The whole of the combustion chamber is water-jacketed, G, although not in communication with the main jacket B, and has a separate inlet H and outlet I; D and E being the supply and outlet to the cylinder jacket, the bridge pieces connecting them with the main supply and outlet pipes. By arranging the areas of the relative openings proportionate to the needs of the combustion chamber and main jacket, a most efficient circulation is obtained. The air valve J and exhaust valve K being in the direct line of the impulse greatly facilitate both the inlet of the charge and expulsion of the products of the combustion; and as the gas entering at L through the channel M meets the inrushing air drawn from the air-silencing chamber O (placed inside the base N) through the pipe P, a pure mixture is ensured at the nearest point of ignition-viz. the igniting port Q, which being a very short one and on the direct line of engine, ensures a very reliable ignition without a timing valve.

R is the gas inlet from the main gas cock L, used for the