HEAVY-OIL ENGINES FOR MARINE PROPULSION. 247 
grade material, that these difficulties can be readily overcome, and without doubt, 
when the builders realize this, there is a possibility that this engine will supplant 
everything else. 
I would like to point out that the fuel pump is one of the most serious points 
‘that has to be considered. It has been found that ordinary bronze or cast iron is not 
nearly good enough for transmitting the oil to the high pressure cylinders. It is 
necessary to take forged steel, if not a high grade of nickel or vanadium steel, and 
forge the barrels of the pumps, so that the walls are absolutely solid and without 
porosity. The valves themselves should be ground and should be so readily acces- 
sible that they can be overlooked on a minute’s notice. It is always necessary to 
provide not only one valve in the suction or discharge lines, but to provide two, 
and even three sometimes. It is also desirable to put the pumps and valves as near 
to the fuel valves on the engine as possible. 
Another point which causes a great deal of difficulty is the fuel needle. The 
fuel needle is very troublesome when it leaks, the flame will strike back and it be- 
comes very hot, and sometimes spots will fuse on the atomizer on the inside, and 
also on the needle itself. It has been the practice lately to make the atomizers of 
bronze or brass on the inside of the point of the needle. It is desirable in these 
places to use a very high grade of steel, and it is possible that a construction can be 
found which will do away with the fuel needle, and that would be a very desirable 
thing to do. 
Perhaps a good many of the members of this Society know that in Germany 
and in Europe in general, I believe, the so-called open-top atomizer has been de- 
veloped within the last few years, and a great many designers since Litzenmayer 
have taken advantage of that, and prefer this construction at the present time. 
The oil is placed in a space permanently in connection with the compression space, 
and it is only air that is admitted by the needle. It keeps the needle back further 
from the point of compression and allows the air to cool the needle point. There 
ate certain advantages in that arrangement, provided the oil flows very quickly 
and cleanly, so that no depositions of carbon can be formed in the open space. 
The shafts are another thing that have troubled the designers greatly, and it 
should be aimed to make the shafts as rigid as they possibly can be made. 
The disadvantage has been held up against the Diesel engine, that it is too 
heavy. I believe that careful designing and careful consideration of marine con- 
ditions can avoid almost entirely that difficulty. The Diesel engine offers itself by 
the handling of pure air for compression purposes only particularly to the 2-cycle 
and the double-acting type. It can be arranged very nicely, and I shall take the 
opportunity of forwarding to the Secretary a sketch that I have made of a Diesel 
engine, that shows fairly large size, 32-inch diameter, by 36-inch stroke, where all 
these difficulties can be overcome. 
I prefer for the frame of oil engines of this high compression type a steel fram- 
ing, which I believe is superior to a cast iron housing or frame, because the stresses 
are always direct tension or compression and therefore a steel column, securely 
