SEA. 



in RoufiUon, and Cape Croifit in Provence, forms a bank 

 above the furface of the water at the fhore, of the cxaA and 

 perfeft figure of an arch ; and within this there is formed 

 another fuch arch, making the bottom of the fea in that 

 place for a very great way from ftiore, which is of different 

 depths in various places, but ufually between fixty and 

 feventy fathom. See ^m-Shore. 



It is a general rule among failors, and is found to hold 

 true in a great many inftances, that the more the Ihorts of 

 any place are deep and high, forming perpendicular cliffs, 

 the more deep the fea is below ; and that, on the conti'ary, 

 level (hores denote fhallow feas. Thus the deepeft part of 

 the Mediterranean is generally allowed to be under tiie 

 height of Malta. The obfervation of the Itrata of earth, 

 and other foffils, on and near the (hores, may ferve to form 

 a very good judgment as to the materials which are found in 

 its bottom. 



The veins of fait and of bitumen doubtlefs run on the 

 fame, and in the fame order in which we fee them at land ; 

 and the ilrata of rocks, that ferve to fupport the earth of 

 hills and elevated places on fliore, ferve alfo, in the f.-ime 

 continued chain, to fupport the immenfe quantity of water 

 in the bafon of the fea. It is probable alfo, that the veins 

 of metals, and of other mineral fubftances, which are found 

 in the neighbouring earth, are in the fame manner continued 

 into the depths of the fea. The particles of metals in this 

 cafe, are probably carried off into deep water, and funk 

 among the fofter matter of the bottom, but fome of the 

 lighter minerals feem to have given colour to thofe beautiful 

 crufts, which are found upon many fea fubftances, and which 

 lofe their luftre in the drying. The fubterranean rivers, 

 and currents of water, make great changes in what would 

 be the natural furface of the bottom of the fea, where they 

 arife, each having a peculiar bafon of its own. We are in- 

 formed by numerous inftances of fubterranean currents, and 

 as we fee them break out in rivers on the furface of the earth 

 in fome parts, fo in others we may be well affured that they 

 break up the bottom of the fea, and empty their frelh waters 

 into the fait mafs. 



In this cafe, the rufliing up continually of fuch a body 

 of water makes a roundifti cavity, and its running fome one 

 way, lengthens and carries on that cavity, till by degrees it 

 is loft, as the frelh water by degrees becomes blended with 

 the fait. Thus every river that arifes in the bottom of the 

 fea, alters the form of its furface, and makes a bafon for 

 itfelf, in which it runs a confiderable way. Many feas near 

 the fhore, and when the water is tolerably clear, fhew the 

 traces of thefe currents to the naked eye from the furface, 

 and the water taken up from them is found more or lefs 

 frefh. 



The coral fitheries have given us occafion to obferve, that 

 there are many, and thofe very large caverns, or hollows in 

 the bottom ef the fea, efpecially when it is rocky ; and that 

 the like caverns are fomelimes found in the perpendicular 

 rocks, which form the fteep fides of thofe fifheries. Thefe 

 caverns are often of great depths, as well as extent, and 

 have fometimes wide mouths, equal to their largeit diameter 

 in any part, but fometimes they have only narrow entrances 

 into large and fpacious hollows. It is the common opinion 

 of the people about the place, that thefe caverns are pre- 

 pared by nature for the circulation of the fea-water ; but 

 that operatian, however neceflary, may be performed as 

 well without, as with thefe caverns, and they feem in reality 

 to be only accidental. 



We daily meet with immenie hollows and caverns, na- 

 turally made in rocky mountains ; and as this part of the 

 bottom of the fea is almoft all rock, and its fides of the 



fame nature, it is no wonder that the fame accidents (hould 

 happen, and like hollows be found, though with no parti- 

 cular intent of Providence in their ufe. Nay, there is this 

 farther reafon to expedl them in the rocks buried under the 

 fea than in thofe in hills, that the latter are in a flate of reft 

 and quiet, whereas the former are in continual reach of 

 water, which will infinuate itfelf into every crack or crevice 

 nature has left in them, and may be eafily fuppofed to have 

 burrowed its way in a fmall hole made by nature, till it has 

 formed of it a very large one. 



From fuch obfervations he infers, that the bafon of the 

 fea was at the creation, or at its fecond formation after the 

 univerfal deluge, covered with or compofed of the fame 

 fubftances, as the furface of the reft of the earth is, that is 

 of rocks, clay, and fand, and other fuch fubftances. Over 

 thefe there is an artificial bottom formed of muddy tartareous 

 incruftations, dead weeds, broken fhells, and other bodies 

 of the fame kind, cemented together into a firm mafs or 

 cruft ; and in thofe places where this cruft has never been 

 formed, or where it has been broken, the bottom of the fea 

 is of the fame nature with the ilrata of the earth. 



The bottom of the fea is covered with a variety of mat- 

 ters, fuch as could not be imagined by any but thofe who 

 have examined into it, efpecially in deep water, where the 

 furface only is difturbed by tides and ftorms, the lower part, 

 and confcquently its bed at the bottom, remaining for ages 

 perhaps undifturbed. The foundings, when the plummet 

 firft touches ground on approaching the fhores, give fome 

 ideas of this. The bottom of the plummet is hollowed, and 

 in that hollow there is placed a lump of tallow ; this being 

 the bottom of the lead, is what firft touches the ground, and 

 the foft nature of this fat receives into it fome part of thofe 

 fubftances which it meets with at the bottom ; this matter, 

 thus brought up, is fometimes pure fand, fometimes a fort 

 of fand made of the fragment of fhells, beat to a fort of 

 powder ; fometimes it is made of a like powder of the feve- 

 ral forts of corals ; and fometimes it is compofed of frag- 

 ments of rocks ; but befide thefe appearances, which are 

 natural enough, and are what might very well be expefted, 

 it brings up fubftances which are of the moft beautiful 

 colours. 



Things of as fine a fcarlet, vermilion, purple, &c. as 

 the finell paint could make them, and as yellow as a folu- 

 tion of gamboge, are common ; and fometimes, though not 

 fo frequently, the matter brought up is blue, green, or of 

 a pure fnowy whitenefs. Thefe coloured matters fometimes 

 feem to have made up the whole bottom or mafs of the fur- 

 face, but more ufually they have been formed upon other 

 things, as upon the mud, or upon larger pieces of fhells, 

 corals, and the like, in the manner of tartareous crufts, and 

 thofe in fome degree refembhng the cruftaceous coats of 

 fome of the fea plants. The colours of thefe fubftances 

 are not merely fuperficial and tranfient, but many of them 

 are fo real and permanent, that they may be received into 

 white wax melted, and poured upon them, or kept in fufion 

 about them ; and when thus examined, they feem as if a 

 proper care might make tiiem of great value, as paints of 

 the finer kinds, where little is to be ufed. 



The fame coloured matters that thus coat the fubftances, 

 found at the bottom of the fea in thefe places, are alfo fome- 

 times found extended over the furface of marine fubftances 

 of the harder kind, which are found in deep water. They 

 are always, in this cafe, in a fort of liquid form, being lodged 

 within, or embodied among a fort of jelly or glue of a 

 tranfparent fubftance, which in thefe cafes perfedly coats 

 over the whole. In this itate it gives the naturalift, who is 

 prefent at the fifhing up of his treafurcs, a tranfient profpeft 



of 



