picked up on the Hoboken docks for the time being, and were given no special training for the tests or for this particular type of boiler. Several firemen were discharged for drunkenness and others taken on during the tests. One water tender, two firemen, and two coal passers were on duty in each shift.

The operation of the boilers and of the firing was supervised by the Company's engineers, who stood watches in three shifts of eight hours each.

The excellent evaporative results obtained indicate the high efficiency possible with the ordinary run of firemen, if properly supervised and directed. This

supervision provided for careful and regular firing, keeping fires level and not over eight inches thick, with proper use of the slice bar and leveling hoe. Special attention was paid to making all the boiler casings airtight.

Methods of Starting and Stopping Tests.-In the first test the alternate method. of starting and stopping the test was employed. In the second and all succeeding tests the flying start was employed, it being much more satisfactory under the conditions required by the contract than either the standard or the alternate methods.

Gas analyses were taken by one of the Company's engineers, closely observed by members of the Board. All other data were taken simultaneously by representatives of the Company and by one member of the Board and the assistants to the Board.

Test No. 1.-At 15 pounds per square foot of grate per hour.
Begun at 6:08 P.M., June 13; finished at 6:08 P.M., June 14, 1910.

Weather during the test, warm and clear.

The blower was not run, the compartment was open, and the steam jet closed.
The evaporation from and at 212 degrees F. per pound combustible was 12.15.
Test No. 2.—At 25 pounds per square foot of grate per hour.

Begun at 8:30 P.M., June 14; finished at 8:30 P.M., June 15, 1910.

The steam jet was partly open. The forced-draft blower was used to ventilate the fireroom, but the compartment was not closed.

Weather during the test was warm and clear, slightly cloudy at the end of the test.

The evaporation from and at 212 degrees F. per pound of combustible was 12.07.

Test No. 3.-At 35 pounds per square foot of grate per hour.

Test begun at 10:25 P.M., June 15; finished at 10:25 P.M., June 16, 1910. The steam jet was partly open. The forced-draft blower was in operation and the compartment closed.

Weather during test, cloudy and rainy.

Rate of evaporation from and at 212 degrees F. per pound of combustible was 11.77.

Test No. 4.—At 40 pounds per square foot of grate per hour.

Test begun at 11:30 P.M., June 16; finished at 11:30 P.M., June 17, 1910. The steam jet was partly open. The forced-draft blower was in operation and the compartment closed.

Weather during the test, rainy during the first twelve hours, clear the last twelve hours.

The evaporation from and at 212 degrees F. per pound of combustible was 11.89.

Test No. 5.-At maximum capacity.

This test was conducted on June 18, 1910.

The fires were lighted with the boiler in following condition:

Temperature of water in boiler, 102 degrees; water level in glass, 11⁄2 inches;

furnaces primed."

Lighted fires at 9:04 A.M.

Steam formed at 9:12 A.M.

Steam pressure 50 pounds, 9 h., 16 m., 30 S., A.M.

Steam pressure 100 pounds, 9 h., 18 m., A.M.

Steam pressure 150 pounds, 9 h., 18 m., 55 s., A.M.
Steam pressure 200 pounds, 9 h., 19 m., 45 s., A.M.
Steam at 200 pounds in 15 m. 45 s.

The test began at 9:38 A.M., and ended at 12:38 P.M.

The steam jet was wide open. The forced-draft blower was in operation, and the compartment was closed.

At the end of this test the fires were hauled and boiler carefully examined. There were no signs of any leaks, and no distortion of any kind, either in tubes baffles or casing, was noticed.

The weather during the test was clear.

The evaporation from and at 212 degrees F. per pound of combustible was 10.33.

FERRYBOAT "HAMMONTON." PENNSYLVANIA RAILROAD. BABCOCK & WILCOX BOILERS. 1100 INDICATED HORSE-POWER

Test No. 6.-At rate of 45 pounds per square foot of grate per hour, with the back end of grate lowered six inches below the level at which it was carried during the previous tests.

Test begun at 10:00 A.M., June 20; finished at 4:00 P.M., the same day.

The weather during the test was clear.

The evaporation from and at 212 degrees F. per pound of combustible was II.30.

THE CHINA MERCHANT STEAM NAVIGATION COMPANY. BABCOCK & WILCOX BOILERS, 2750 INDICATED HORSE-POWER

The curve of rate of evaporation appears to show that there is a very small falling off in efficiency until a consumption of about 45 pounds of coal per square foot of grate per hour is reached, and that the boiler is almost as efficient at high rates of combustion as at moderate rates under natural draft. This is a highly gratifying result and indicates that the system of baffling is very efficient.

The difference in evaporative results, with the original grate and with the back of grate lowered, is insufficient for determining whether there is any actual advantage or disadvantage due to the lowering of the grate, when coal alone is used for fuel.

The Board reports that the sample boiler tested, representing the type of boiler to be supplied for use on board the U. S. S. "Arkansas" and the U. S. S. "Wyoming," has fully met all requirements of the contract as to evaporative efficiency, and recommends the approval of this type of boiler for general use in the naval service.

SIX BABCOCK & WILCOX BOILERS OF S. S. "MATSONIA OWNERS: MATSON NAVIGATION CO. OF SAN FRANCISCO