FIFTEENTH ANNUAL MEETING. I9 



or drum, which holds about 4000 fathoms. Wlien a sounding is 

 to be made, a brass cup is attached to the end of the wire to 

 catch and bring up some of the bottom, that its composition 

 may be observed. Just above the cup is a thermometer which 

 records the temperature of the deep water. To the above-men- 

 tioned cup a heavy shot is fastened to accelerate the downward 

 motion. When a sounding is to be taken the ship is kept 

 stationary, that the wire "may be straight up and down, and. 

 everything being ready, the weight sinks rapidly to the bottom, 

 The concussion caused by striking the bottom detaches the 

 heavy weight, at the same time the cup grasps a portion of the 

 bottom's surface, and a donkey engine turns the cylinder, where- 

 by the wire is quickly reeled in. Each sounding station is 

 given a number, and a record is kept of the depth of the water, 

 the nature of the bottom and the temperature at that depth. 



A long article might be written on the various appliances and 

 mechanisms of the ship, but it would be too great a digression 

 from the subject originally proposed. Most worthy of mention, 

 however, are the annunciators on the upper deck, placed against 

 the wheel house. These are two contrivances, one for the star- 

 board engine and a similar one for the port engine, which indi- 

 cate to the officer of tlie deck the movement of both engines. 

 This is also an invention of Engineer Baird, as is, too, the 

 process by which the ship is furnished with a never failing 

 supply of pure, fresh drinking water distilled from the salt 

 water. Neither must I omit to mention the ship's boats which 

 form so important a part of her equipment. A steam launch, a 

 steam "gig," and numerous row-boats render effective service 

 when in harbors. Now, as to deep sea dredging. Just forward of 

 the wheel house, attached by one end to the foremast, is a boom 

 capable of being raised like a derrick and swung over the side. 

 Just below this boom is a donkey engine, and below that, in the 

 hold of the vessel, is coiled a strong, wire cable, about one-half 

 inch in diameter and about four miles long. This runs along 

 the under side of the boom and over a wheel at its free ex- 

 tremity. To this end of the cable is attached the dredge, or 

 trawl, as it is sometimes called. This consists of a strong, 

 baggy net, fastened to what looks like a pair of huge iron sleigh 



