676 



A FEW REMARKS 



after the first few hundred fathoms, the deeper it penetrates ; if 

 not the increased resistance to sinking, found by the weight 

 and line? " Friction, caused bypassing through the water,"" I 

 may be told. Can that friction be compared with the augmented 

 tendency to sink that would be given by the continually increas- 

 ing weight of line, if the water did not increase in density ? 



The pressure of the column of water over any weight, after 

 it has been sunk some hundred fathoms, is shown by the time 

 and exertion required to haul it up again. The operation of 

 sounding in very deep water, with any considerable weight, 

 occupies several hours, and a great number of men. That 

 water is elastic has been proved by Canton's experiments as well 

 as others : but there are familiar illustrations of this fact visible 

 in ricochet shot, in ' ducks and drakes,' in the splashing of 

 water, and in the rebounding of rain-drops from water. Being 

 elastic, and the lower strata being under enormous pressure, it 

 follows that those strata of water must be more dense than the 

 body above them. No one doubts that the lower regions of 

 the atmosphere are denser than the higher ; yet air is but a 

 rarer and much more elastic fluid than water. That which 

 takes place in air, to a great extent, may be expected to occur 

 in a very diminished degree with water. If it were not so, why 

 should stones be blown up, casks violently burst, or rocks 

 suddenly torn asunder by the application of the principle 

 usually described as the hydrostatic paradox .'' If the water 

 were not highly compressed before the explosion takes place, 

 would there not be a gradual yielding, a tearing asunder by 

 degrees, instead of a sudden and violent bursting.? 



The object of this digression is to show that although bodies 

 whicli are not buoyant may sink to a considerable depth, it 

 does not follow that they must sink to the bottom. Each 

 separate thing may sink a certain distance, in proportion to its 

 specific gravity, and there remain. The greatest depths evei* 

 reached by heavy weights, attached to lines, do not exceed a 

 mile and a-half; a small distance, probably, compared with the 

 depth of the diluvial flood. 



Although metals, stone, rock, or coal may have sunk deeply in 



