701 
The Trials of Oil Engines at Cambridge. 
Hornsby's engine injects the oil into an unjacketed portion of 
the cylinder itself, where it is vaporised and ignited by the heat 
engendered by the previous explosion. All the other engines 
employ a separate vaporising chamber of some sort, into which 
the oil is pumped or flows by gravity, and from which, at the 
suction stroke, it passes as vapour into the cylinder, meeting 
there the additional supply of air required for its complete 
combustion. 
It is somewhat remarkable that, with such varied methods 
of vaporisation, not one of the engines was found to be clogged 
or unduly fouled after the severe tests to which they were put. 
No tarry or sooty deposit was accumulated in any instance, 
THEhORNSBY-AKRoVD" PATENT SAFETY OIL ENGINE 
•niiinniiiiiiii 
Fig. 1 . — Hornsby’s Fixed Oil Engine (First Prize). 
and it may be fairly concluded that difficulties from this source 
are no longer to be feared in a well-designed oil engine. All 
the engines worked on the “ Otto ” or “ Beau de Rochas” cycle. 
General Description of the Engines. 
Messrs. R. Hornsby & Sons, Ltd., Grantham. — In fig. 1 is 
given an external view, and in fig. 2 is shown a section through 
the cylinder and valve-box, of Messrs. Hornsby’s engine (First 
Brize, 50/.). It is an 8 brake horse-power engine, costing 
170/. complete. The vaporiser forms a prolongation of the 
cylinder of Q shape, and is enclosed in a movable iron casing. 
The oil is injected into this chamber, with a little air, at the com- 
vol. v. T. s. — 20 3 A 
