656 REPOKT OF COMMISSIONER OF FISH AND FISHERIES, [52] 



for an oil-filter ; the steam and water enters at the top and the con- 

 densed water escapes through the valve ; the steam does not escape. 



We substituted this for the Chapman trap for draining the after 

 heaters, and find it works admirably. 



COAL. 



Excepting 30 tons of semi-bituminous coal purchased at Nassau in 

 April, and about two tons for the cutters, we have used anthracite coal 

 exclusively. 



The total consumption, for all purposes, has been 953 tons 419 pounds, 

 and the average cost has been $5.17 per ton. 



The quality has been generally good, except that obtained from the 

 Norfolk navy yard, which we found dirty and air-slaked. 



We check the weight of coal received by the increase in the ship's 

 displacement, which latter quantity is obtained from a calculation of 

 the ship's increase in draught of water. We either witness the weigh- 

 ing of every pound of coal we buy, or weigh it ourselves as it is deliv- 

 ered alongside the ship. The following amounts of coal have been used 

 for the purposes specified : 



Tons. 

 Coal consumed to propel the ship while on her course, to warm the ship, 



pump bilges, wash decks, and hoist ashes while tho maiu engines were in 



operation 662§|^$ 



Coal consumed to light the ship by electricity 14£fH 



Coal consumed to ventilate tho ship lOJMo 



Coal consumed to distill water 23£§3$ 



Coal consumed by the steam cutters 9f 1 'i $ 



Coal consumed for driving the hoisting engine, steam windlass, washing 



decks, warming ship, and keeping fires banked when the main engines 



were not in operation 277 r ./ r , T 



Total coal consumed by the engineer's department 899^& 



Coal consumed by the equipment department (cooking) 53£§f$ 



MEDICAL DEPARTMENT. 



Report of Surgeon J. M. Flint, U. S. Navy. 



The general health of the ship's company during the year has been 

 very good. No cases of serious illness have occurred, and only those 

 trifling accidents incident to all the ruder occupations of men. The 

 provisions for ventilation are the same as heretofore, and are reason- 

 ably effective when in use. The between-decks, in this as in all other 

 ships with which I have been acquainted, are more or less malodorous 

 at sea. No precautions can prevent the evolution of foul gases in the 

 bilges of a ship, where the presence of organic matter and the condi- 

 tions of heat and moisture favorable to decomposition are unavoidable. 

 How to remove these gases before they have contaminated the air of 

 the apartments of men and officers, is a problem not yet solved j it is 



