194 MACHINERY AND TRIALS OF THE PASSENGER SHIPS 
trials of the American Legion, in which vessel the arrangement of the blowers is similar to 
that in the President Pierce, in which the blowers are of the vertical spindle type, as shown in 
Mr. Warriner’s paper, and, I understand, take their suction from the deck above and dis- 
charge horizontally into the upper part of the fire rooms. This arrangement does not lend 
itself to a cool fire room, as was found on some of this class of vessels. In the President 
Cleveland class the blowers are of the horizontal type and take their suction from the ventila- 
tors above and discharge down the ventilators to the fire rooms, thus bringing fresh air down 
to the crew on the fire-room floor. This gives an efficient arrangement as far as ventilation 
and operating conditions in the fire rooms are concerned. 
The temperatures are given in Plate 61 and are as follows: 
President Jackson, 85° F.; President Cleveland, 80° F.; President Pierce, 113° F.; 
American Legion, 131° F.; and President McKinley, 94° F. 
The air pressure during the trials of the Newport News vessels was less than on the 
President Pierce. The superheaters fitted in the Newport News vessels were of the Babcock 
and Wilcox type, and I would call attention to the temperature of the stack in these two 
vessels, which varied from 483° to 468° F., which is very good, and indicated efficient 
operation. 
The President Cleveland was fitted with calibrated feed measuring tanks. There was a 
six-hour trial, and on the first four hours of the trial the steam consumption of the main tur- 
bines only was measured; on the last two hours the entire feed was measured, so as to give 
a line on the consumption of the auxiliaries. For the main turbines, during the first four 
hours, the consumption was 10.54 pounds as against 10.7 pounds given in Mr. Warriner’s 
paper; and for the auxiliaries 2.46 pounds as against 2.74 pounds in Mr. Warriner’s paper. 
The oil consumption measured by calibrated meters corrected to the basis of 19,000 British 
thermal units per pound was .935 pound and .941 pound respectively on the two Newport 
News-built ships. 
I might say that these trials were run off the Virginia Capes in water of from 7 to 15 
fathoms. A comparison of data from sister ships of approximately the same displacement 
on trials run off the Virginia Capes in one case, and the Delaware Breakwater in the other, 
indicates that from 4 to 10 per cent more power is required for the same revolutions on trials 
off the Virginia Capes due to the shallow water. The trials of the President Cleveland were 
run five days after the vessel was docked, and the trials of the President Jackson twenty-two 
days after docking. 
I wish to say something about the gears, on which very little data are given. The gears 
fitted in the two Newport News ships were about the same diameter of main gear and pinion 
as were installed in the Bethlehem Company ships, but with more face, the Newport News 
ships having 42 feet face as against 36-feet face of gears fitted in the President Pierce. 
I would like to state that the contract speed of these ships was 16 knots. The machin- 
ery was guaranteed to make 12,000 horse-power. We all understood and knew that this 
power would drive the vessel at more than 16 knots. A few days ago I was informed by 
one of the Shipping Board Commissioners that several of these ships are making over 18 
knots sustained sea speed. I informed the commissioner that we would not advise opera- 
ting these gears at this power, as we believed that they would not be entirely satisfactory if 
so operated in continuous service. 
I think it would be interesting to hear from Mr. Warriner as to the cast steel main 
gears which were fitted in the President Pierce, and to be informed if these gears are giv- 
