90 
BULLETIN OF THE UNITED STATES FISH COMMISSION. 
31. REPORT OF THE ENGINEER’S DEPARTMENT. 
BY C. R. ROELKER, 
Passed Assistant Engineer, U S. Eavy, in charge. 
The following statement shows the work done in the engineer’s department of this 
vessel from July 1 to October 21, 1888: 
Total time covered by present report days 
Total time the fires were lighted in main boilers hours 
Total time the fires were lighted in donkey boiler do 
Total time the engines were in operation, including time spent in sounding, 
dredging, getting under way, etc hours 
Total time the engines were in operation, with vessel on her course do 
Total revolutions made by engines with vessel on her course: 
Starboard engine number 
Port engine do 
Mean revolutions made per minute do 
Total knots run do 
Mean knots run per hour do 
Mean slip of screws per cent 
Weight of fuel consumed in main and donkey boilers tons 
Weight of fuel consumed in steam cutters do 
Weight of fuel consumed in galley do 
Total weight of fuel consumed do 
Amount of refuse in fuel consumed. per cent 
Total weight of fuel consumed while engines were in operation tons 
Mean number of pounds of fuel consumed per hour pounds 
Total time the dynamo has been in operation hours 
113 
2,486^8- 
240^8 
1 , 311§8 
1 , 07818 
4 , 249 , 444 
4 , 243 , 530 
65.5 
8 , 771.1 
8.13 
15.33 
636M88 
12|if8 
652 ^% 
15.3 
52im»o- 
890 
566|g 
The maiu engines have worked quite satisfactorily, notwithstanding they were fre- 
quently subjected to severe strains. A single main boiler has been used at a time; 
up to July 13 the full grate surface of each boiler (58J square feet) was used; after 
that date the grate surface was reduced to 45 square feet by bricking off 18 inches at 
the back of the grate in each furnace. Leaks have developed again in the bottom of 
the boilers, and some blisters have been formed in furnaces and back connections. 
The fuel used during this cruise has been mainly Wellington and Nanaimo coal. 
The rapidity with which these coals ignite and produce steam is of special advantage 
when this vessel is engaged in sounding and dredging, and the demand for steam is 
intermittent and irregular. The large volumes of black smoke and soot produced are 
not only a source of annoyance and necessitate frequent sweeping of tubes and con- 
nections, but cause serious trouble, as the soot in the smoke-pipe ignites easily. The 
Wellington coal, which was mostly procured fresh from the mines at Departure Bay, 
Vancouver Island, gave results in steaming efficiency only slightly inferior to Welsh 
coal. Great precautions are necessary to prevent the spontaneous combustion of this 
coal in the bunkers. At Astoria, Oregon, smoke was observed to issue from the after 
port bunker. It was found that the rope covering on the auxiliary steam pipe was 
completely charred, and that a great heat had been develoj^ed in the surrounding coal. 
No actual ignition of the coal had taken place. The rope covering has been removed 
