174 BULLETIN OF THE 



ommended by Sir William Thomson, namely, steel piano-forte wire, No, 

 22, Birmingham gauge, weighing 14|^ lbs. to the nautical mile. The 

 friction line should be ^ inch or slightly less in diameter, and should be 

 oiled or kept wet with water where it comes in contact with the friction 

 score of the reel. 



To take a Sounding with the Machine. 



The reel, containing the wire and stray line, being in its bearings, 

 reeve the end of the stray line up over the cross-head pulley, from 

 inboard to outboard, and then down through the guide which forms part 

 of the attachment of the swivel pulley. Bend on the end of the sound- 

 ing-rod. Ship the pawl into the ratchet-wheel, which is on the axle of 

 the reel. Place the friction line over the friction score, as shown in 

 the figure, and from the scales reeve it under the pulley Y, on the 

 same side of the machine as the friction score, then up and over the 

 pulley Q, and down under the other pulley Y (Figs. I., IIT., V.). Haul 

 the cross-head well down on the guides, against the resistance of the 

 accumulator springs G, G (Fig. II.), so as to insure a large surplus of 

 friction on the reel at the time of starting the sounding. Make fast the 

 hauling part of the friction line to the cleat Z (Figs. I., IV., V.). Con- 

 nect the sinker with the sounding-rod, and get it overboard, letting the 

 stray line take the whole weight. See that the register and odometer 

 are properly set. Attend the friction line, throw back the pawl, and let 

 the reel revolve slowly until assured that everything is working well, 

 when ease up the friction line and follow out as nearly as practicable 

 the rule governing the amount of resistance to be applied to the reek 

 If a weight has been attached to the stray line to prevent the kinking 

 of the wire, be particularly careful not to let the reel revolve fast until 

 this weight is through the guide. Avoid any stoppage just as the end 

 of the wire is leaving the reel, as it is not prudent to subject a very 

 short length of wire to the torsion that may be caused by the spinning 

 around of the sinker in the water. It is impossible to say how fast the 

 wire may be allowed to pay out, since the limit of safety varies with 

 circumstances, and depends on the state of the sea and the extent and 

 rapidity of the ship's rolling and pitching motions. The drawback to 

 quick work with the original machine lies in the tendency of the wire 

 to fly off the reel — and kink or break — during the downward plunges 

 or rolls of the ship. The strain at such times is very much relieved 

 from the wire ; and, in a moderately heavy sea, should the reel be re- 

 volving fast, it is sometimes not slowed down in time to prevent tho 



