208 EEPORT OF COMMISSIONER OF FISH AND FISHERIES. [92] 



top, sides, and bottom are double sheathed, and coatain a 4 inch air 

 space, which is filled with sawdust; they are lined on the inside with 

 galvanized iron, and all joints are carefully soldered. A trap in each 

 compartment drains all water into the bilge. The ice-houses are reached 

 by hatches from the bertii-deck. The cold-room B is immediately 

 abaft the ice-house and communicates with it by apertures near the top 

 and bottom of the after bulkhead of the icehouse, as shown by the ar- 

 rows €, e. Gratings, c, c, c, c, which are in sections, and can be easily re- 

 moved and cleaned, are used as shelves on which the natural history 

 specimens or articles of food can be placed. The structure of the cold- 

 room is precisely similar to that of the ice-house, except that the air- 

 space is filled with hair-felt instead of sawdust. This space, just as in 

 the ice house, is divided by a longitudinal bulkhead, thus allowing two 

 independent compartments, each with its door in the after bulkhead. 

 The air of the ice-house becomes chilled, falls to the bottom of the 

 chamber, and precipitates its moisture, while the air in the cold-room, 

 whose temperature is greater than that of the ice-house, and con- 

 tains consequently more aqueous vapor, rises; thus a constant current 

 is established between the chambers, and passes through the apertures 

 marked by the arrows. That the air in the cold-room does take up and 

 remove moisture has been shown by the simple experiment of placing 

 wet cloths on the gratings, and which onreiooval a few hours later were 

 found to be comparatively dry. Fresh food tor twenty- five persons for 

 twenty days has been carried, and this quantity could be largely in- 

 creased. When the ice-house is kept well filled, the temperature of 

 the cold-room is about 40° F. 



Berth-deck. — On the forward part of this deck are the magazine, brig, 

 &c. This deck is 40 feet long, 7\^ feet between decks, and has a cubic 

 capacity of 16,000 feet; it is laid with yellow-pine lumber which was 

 thoroughly seasoned before it was put into the ship, and consequently 

 its capacity for absorbing and retaining moisture for hours after wash- 

 ing down is limited; the rapidity with which the deck dries can be 

 greatly increased by starting the blowers immediately after drying 

 down, and observations have shown that in a short time after starting 

 these, the atmospheric conditions of berth and spar deck are alike. 

 During the past year this deck has not been wet on an average more 

 than twice a week. On this deck forty-four of the crew swing, and all 

 the men are messed ; they are provided with swinging tables and with 

 benches, which can in a very short time be stowed away ; the comfort 

 of the crew is immensely promoted by the substitution of tables and 

 benches for mess-cloths. The deck is well lighted and ventilated by 

 two hatches, the larger of which is 6-fy by 6^^ feet, and a smaller one 

 3^ by 3-1% feet; by four air-ports on each side, circular in shape, and 

 9 inches in diameter, and by six registers for artificial ventilation. Two 

 steam-pipes, running to and from anchor and reeling engines, pass through 

 this deck; their presence is sometimes an advantage and sometimes 



