"^32 DEEP-SEA SOUNDING. 



the angle it makes with the surface of the sea also well noted, and 

 these evidences accord so nearly with the calculations made for water in 

 a quiescent state, that it is now beyond controversy, that rapid motion is 

 confined to the upper strata. 



Sir James Eoss, in the Arctic Expedition of 1818, used a 2^-inch whale 

 line for sounding, and devised a " deep-s«a clam " for securing samples of 

 the bottom, which closed by a falling weight on striking the ground. In 

 later years, the line was carried down by a weight or spherical shot, 

 suspended on a peculiar pair of hooks, the invention of Mr. Bonnioi ; 

 when it touched the bottom, the hooks gave way automatically and 

 dropped the weight. Lieut. Brooke, U.S.N., devised an improved form 

 of this apparatus, the detachable weight sliding on a tube, which latter 

 secured a specimen of the bottom. Lieut. Dayman used an improvement 

 of the latter, on the Cyclops, in 1857. In the same year, the U.S.S. Arctic 

 made successful use of the Massey Sounding Machine, which registers the 

 depth on a dial attached to a revolving fan. 



In H.M.S. Bulldog's soundings, in 1860, the depth was obtained 

 generally by cod-line, with an iron sinker of 118 lbs., the line and sinker 

 being lost at each sounding. The depth being thus obtained, a machine 

 for bringing up a sample of the bottom was next sent down by a stronger 

 fine, with a self-detaching tubular sinker of 100 lbs. The apparatus which 

 brought up specimens of the bottom was a double scoop, 5 inches in 

 diameter, kept open so long as the weight was dependent on it, but 

 forcibly closed by means of a vulcanised india-rubber band the moment it 

 was detached by touching the bottom. This brought up specimens in large 

 quantities. It was contrived by Dr. Wallich and Mr. Steil, the assistant 

 engineer, and has been called the Bulldog Machine. 



The "Hydra" Sounding Machine was invented by a blacksmith on 

 H.M.S. Hydra, 1868, and this was employed on H.M.S. Porcupine, in 

 1869, for the deep soundings. Its peculiarity consists partly in the 

 simple means of detaching the weights, a compressed spring relaxing and 

 letting go the line which supports them ; and partly in the construction of 

 the rod which carries them, this being a strong tube furnished with valves 

 opening upwards, so as to allow the water to stream through it freely in 

 its descent, whilst they enclose the mud or sand into which the tube is 

 forced on striking the bottom before the sinkers are detached. For depths 

 of 1,000 to 1,500 fathoms, two sinkers, each of 112 lbs., were employed ; 

 and for yet deeper soundings three sinkers were used. This apparatus, as 

 modified by Lieut. 0. W. Baillie, B.N., was also used on H.M.S. Chal- 

 lenger, the sounding-line being 0-8 inch in diameter, made of the best 

 Italian hemp, and bearing a strain of 12 cwt. 



The U.S. steamer Blake used the " Sigsbee-Belknap " apparatus, diflfer- 

 ing principally from the foregoing in the means of detaching the sinkers. 

 The sounding line used was of wire, No. 20 guage, capable of bearing a 

 strain of 240 lbs., and carrying a sinker weighing 60 lbs. 



The latest sounding machine, now in general use by telegraph and 

 •other deep-sea exploring vessels, is that devised by Mr. Lucas, of the 

 Telegraph Construction Company. A complete apparatus, for depths up 

 to 6,000 fathoms, weighs less than 2 cwt,, the wire weighing about 14 lbs. 



