On Massey's Sounding Machine, g5 



about two feet long by means of the screw I, and by 

 means of a prolongation of the brass plate at j, to which 

 a nut is screwed on the opposite side of the bar. This 

 prolongation acts as an axis or centre in the iron bar, to 

 enable the brass plate to move between two small cheeks 

 at /, the screvv at i going through the two cheeks and 

 plate at right angles with the surface of the plate, thus 

 allowing the jilaie to move between the cheeks for the 

 space of about an inch to obviate the eddy of the plate. 

 The line is fixed at m, and the lead is cast on to the bar 

 about an inch below y. The brass plate projects about six 

 inches, lesi the rotator should be affected by the eddy of the 

 lead. 



When the machine reaches the ground, or is attempted 

 to be drawn up again, the rotator falls into the position be- 

 low c, which prevents the rotary motion, but as an addi- 

 tional stcmity a locking plate d is acted upon by a bolt 

 which is fixed to and put in motion by the flirt piece t. 

 During the descent, the flirt piece is kept in an upright 

 position by the water, but ceases to be so when the ma- 

 chine becomes stationary or is hauled up. 



Thus it appears that the whole of the apparatus, which 

 leally indicates the soundings, is comprized in the space of 

 about one foot, that is to say, from the summit of the ro- 

 tator to the locking plate, without any dependance on the 

 Jength of the line or rate of sailing. 



Such is the description of the niachine. No sooner was 

 it completed, tiian it was judged to be of sufficient cor- 

 rectness to stand the test of the severest trials. Testimonies 

 are frequently obtained on very light grounds ; but those 

 ohtained for this machine are of a very different stamp. 

 Captain Malcolm, of the Royal Navy, having used Mr. 

 Massey's log* during his passage to and from the West 

 Indies, recommended the sounding machine to the attention 

 of Admiral Montagu, who commanded at Portsmouth. 

 The admiral ordered " the masters of His Majesty's ships 

 the Royal IViiiiam and Hesista/ice to proceed off the Isle 

 of Wight, for the purpose of trying the correctness of the 

 machine;" and the joint report of the masters in date 2{)th 

 June ib06, was, that <♦ sailing at the rate of 5§ or 6 knots 



• Capt. Malcolm, in a letter of the I2th of May 1 ROR, says. " I used the 

 Log Macliine during my passage to and from tlie West Indies, and found 

 it gave the stiip's run perfectly correct." The captain had purcliased it of 

 Capt. Whittle, of the merchant service, who h;jd carried the log out from 

 Liveipocil to Newloundlaiid, from thence made C.ipe St. Vincent, with aa 

 errar o:ily of /uo 7niUi, aud thcu proceeded to Naples, where he sold it to 

 Capt. Malcolm. 



they 



