i>i;i:r-si;.\ i:.\i'i,(ti;A i ion. 115 



Sciciitilk- navigators, ill an early |»cri()il. hruan to att(iii|it 

 ini|ti(>vrincnts in sounding apparatus lor i^ivat dcittlis. In 

 this Held tho offic-ers of our own navv havi* stood easily lirsl, 

 not only in order of [)riority of invention, but also in the 

 porfcM'tion of the results attained up t(» the present time. 



An early inii>roveinent was the substitution, in i)laee of 

 the ordinary U-ad-iine, of a very line lini' and a very heavy 

 weifj^ht. whieli ran out ra|)idl\', and wa< not intendei] to be 

 rei'overed, l»ut was eut at the surfaee. The chan;j;e in the 

 rate of runniuii- out of the line indieatcs when bottom is 

 reaehcd. I have thus sounded in depths of over a mile 

 witjj satisfaetory results. But the nature, as well as the dis- 

 tanee, of the bottom, is an important feature in such investi- 

 gations, and .sounding instruments, which would {)ick up a 

 good-sized sample of tlie bottom at the depth of a mile or 

 more, and bring it safely to the surface, were tlie next in 

 order of invention. Sir John Ross, as early as 1818, in- 

 vented a " elamm " something like an old fashioned i)air of 

 .sugar tongs, which should be closed by a falling weight on 

 striking the bottom. The same idea, in different forms, has 

 since been tried l)y several inventors, but it has never 

 proved satisfactory in the long run. A piece of gravel or 

 shell gets between the edges of the tongs, hold them apart, 

 and the contents are washed out while hauling in. Sir 

 .lohn Ross, however, succeeded in several cases in briuEfins: 

 up several i)Ounds of the bottom, once with some animals 

 contained in it, from depths of over five hundred and pos- 

 sibly one thousand fathoms. Modifications of this princi- 

 ple are found in the .so-called '" Bulldog " and " Fitzgerald " 

 .M)unding instruments, both of which have been well .spoken 

 of for their performances on certain occasions, but which 

 have not ijorne the test of greater use. 



The first important advance in this direction was made 

 by Midshipman .lolni M. Brooke, U.S. N., in 1854. It should 

 be stated that in addition to the difficulty of getting the 

 weight and line perpendieularly to the bottom, and know- 

 ing when the bottom has l)een reached, another important 

 featiu-e in .sounding work is the recovery of the line and 



in 



