194 $ ir Hans Sloane to Mr. Ray. 



was very ftrong, and fomething noifome. If one look 

 earneilly on fome Pieces of this Clay, there are eafily 

 difcernable feveral fmall Quantities of a bituminous 

 Subllance, brownifh Colour, and tough Confidence. 

 I doubt not but this Subftance gives the Smell, and 

 other Qualities, to this Layer. This Clay preserves 

 its Scent a pretty while, tho' by Degrees it grows 

 fainter j and being expos'd to the Air for about a 

 Month, will lofe it quite. Eight Pounds of this Clay 

 dfftiird in a Retort, plac'd in a Sand-Fire [3d Degree 

 of Heat] yielded one Pound of Phlegmatick Liquor, 



and fix Drams of Oil, of a quite di fferent Smell from 



any thing I have hitherto met with. 



The fecond Layer was Gravel, which reach'd from 



3 and a half to about 4 and a half deep, or thereabouts, . 



It very much refembles the other in all its Qualities, 



except the Noifomnefs of its Smell : It lofes its Scent 



much fooner than the former. 



The third Layer was an earthy Sand, which fmelb 



ftronger than the other two, and withal is much more 



fragrant : The deeper you dig, it fmells the ftronger. 



1 took 8 Pound of this Layer at 9 Foot deep, and 

 filPd a Retort with it, and plac'd it as the Clay 5 but 

 it afforded only 6 Ounces of Phlegmatick Liquor, and 



2 Drams of Oil. This fandy loofe Earth quits its 

 Scent in about a Fortnight, being expos'd to the 

 Summer- Air. 



Confidering that Waters owe their gr'eateft Dif- 

 ferences to the feveral Soils through which they pais, 

 I was very defirous to fee what Sort of Waters would 

 be produc'd by their being percolated through fuch 

 a Strainer as this ftrange Sort of Earthy and defiling 

 the Owner to dig till he fliould find Water, he ac- 

 cordingly did y and when he came to about 1 8 Foot 

 deep, Water came in very plentifully s condition'd as 

 follows. 



It had at Top a curioufly colour'd Film, the Co- 

 lours of it refembliDg thofe of the Rainbow : Under 



this 



