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be more distinct and for this same reason the twisted wire requires a heavier weight than the 

 single wire. 



For more than one reason it is necessary that a vertical position of the wire close to 

 the ship should be maintained. In the first place to obtain a correct depth by the counter. 

 In the secoml place for the better working of the upper part of the wire. To make this clear 

 il should be observed that a true vertical position of the wire is only possible if the ship is 

 lying absolutely still as the whole mass of water in which the ship, wire and lead happen to be. 

 As a rule this is not the case and owing to the different motions in the water the wire will be 

 bent even although the upper end of the wire remains vertical. The indications on the counter 

 will therefore always be more than the actual depth and it is impossible even to guess to what 

 extent. In general it can be accepted that the fault is of no consequence when piano wire is used. 



UPKEEP OF THE SOUNDIXG MACHINE. 



The sounding machine should be kept in good condition, well cleaned and oiled. The 

 sounding wire which is being used should be well driecl by passing it through rag, and oiled 

 by passing it through a second rag. The oil reservoir under the lower guiding pulley was 

 seldom used. The original shape of this reservoir proved to be unpractical. The oil being thrown 

 out by the action of the pulley in a very short time even after the addition of vertical plates 

 to the front and back of the reservoir to prevent the oil being thrown out. The wire carries 

 so much oil with it that on reaching the winding-drum gets thrown about and lost. 



Experience tought that by the use of a dry and oiled rag, the oil being used being 

 mineral, the wire could be kept in a good condition. After a whole year's use the piano wire 

 showed no signs of wear. Even the twisted wire showed little or no signs of rust although 

 several times some of the wires got broken. 



New piano wire should be stored in a dry place and packed in water-tight oiled paper. 

 From time to time the wire should be inspected any signs of rust amoved and oiled afresh. 

 \\ ire which had been used in the machine was stored in this manner with good results only 

 with an occasional oilingf. 



THE MANOEUVRING OF THE VESSEL WHEN SOUNDING. 



While sounding the object was always to keep the line vertical. 



In many instances the direction and the approximate force of the current could be 

 estimated fairly accurately. 



Bearing these points in mind and taking into account the probable drifting to be expected, 

 the ship was brought in a direction so as to minimise the chances of the rope deviating 

 athwartships and rather to bring the line away from the ship than towards it. 



