SPRINGS, RIVERS, CANALS, LAKES, 



quadrangular, like grains of salt; which made him suspect, that 

 these petrificatious contain, besides metalline, a great deal of saline 

 particles, whose sides being strongly attracted to each other, and 

 close!) joined, hinders the tire from expanding ihe pores of these 

 Stones, and their being reduced to lime. This alack stone, when 

 broken, appears through the microscope very beautiiul, and like 

 cloth of silver, the pores aud vessels of the wood being filled with 

 white minute crystals. 



Of these stones Mr. S. had some with wood outwardly continuous; 

 others with wood inwardly ; one, the least, part is of stone, the rest 

 wood ; another vL'e versa ; another entirely wood, except a thin 

 coat of stone on one side, which appears to be the very bark; one 

 stone which at one end distinctly shows the annual ringlets of the 

 wood ; one that shows the wood, before it was petrified, had been 

 bent, and partly broken, the fissure being filled \>it!i a sparry mat- 

 ter, and appears plainly from the present appeara.-ire and position of 

 the fibres of the stone. Some of these stones strike fire with a steel, 

 and others by a strong collision, emit a train of sparks. Some of these 

 stones show the grain of holly, ash, and iir. fie had only one piece 

 of oak petrified, easily distinguished by its grain ; it shows the very 

 knots of the wood where young twigs were cut ; and has a hole 

 made through it before it was petrified. 



As for these stones being fit for sharpening or setting of razors, 

 &c. the black ones are rather too hard, and the white ones too oft. 

 The whetstones or hones, vulgarly so called, which aie sold for 

 Lough-Neagh stones, are none of these, but of a sott gritty kind, 

 and found near Drogheda. 



When these stones with wood continuous are taken out of the 

 water, mud, or clay, the woody part dries, cracks, aud falls away; 

 which is the reason why few can be well preserved ; and besides, 

 every body, unwilling to trust their eyes, will touch and scrape the 

 wood, aud thus destroy the most curious part of the stone. 



[Phil. Trans. Abr. 1746'.] 



We have copied the preceding paper, not more for the curious 

 and unquestionable fact it contains, than to exhibit a proof of the 

 infant state of mineralogy not longer ago than the middle of the 

 last century. The above paper is succeeded in the same excellent 

 journal by another on the same subject^ furnished by the justly ce- 



