VOL. XLIV.] PHILOSOPHICAL TRANSACTIONS. 283 



country, these excepted, grows to that vast size ; at least it is certain that holly 

 never does." 



But how Mr. Smyth came to be convinced, that these trees were oak, and not 

 holly, and yet was not convinced of the petrific quality in some parts of the 

 lough, though these trees were found petrified in its mud, is amazing : for if a 

 team of oxen could scarcely draw them from thence, it must be as hard to draw 

 them fi-om any adjacent ground (where they must have grown, lain, and be petri- 

 fied) into the mud of the lake, where they were afterwards found: for it must be 

 supposed, that either these trees grew on the banks of the lake, and, through 

 age, or any other accident, fell into the water or mud, and were there petrified; 

 or that, with great labour and expence, they were brought into it from some ad- 

 jacent ground, after their actual petrification, which is hardly to be supposed. 



Mr. Smyth tells you further, that " Two gentlemen of the north of Ireland 

 where this lough lies, had told him, that they had seen the same body, partly 

 wood, and partly stone; but the only reason for thinking so, being the diversity 

 of colours, which might well enough proceed from several degrees of petrification, 

 we may properly think them deceived; for they made no experiment on that part 

 which tht;y reputed wood. The bark is never found petrified, as he was informed 

 by a diligent inquirer; but often somewhat rotten about the stone, answerable to 

 the bark." 



Mr. Smyth contradicts himself no less in his last supposition, than he did in 

 the first. His friends assured him, that they had seen one or more of the Lough- 

 neagh stones partly wood and partly stone ; but they were deceived, he says : the 

 diversity of colours, by which they judged one part of the stone by its colour to 

 be wood, and the other part likewise, by its colour different from the other, to 

 be stone, were no more than different degrees of petrification. What are we to 

 understand by these different degrees of petrification ? by this something rotten 

 about the stone often found } if not, that some part of the wood was actually 

 turned into stone, some other part in a degree less petrified, and some other part 

 not petrified at all, as these gentlemen assured him : the diversity of colours, 

 seeing and feeling, was enough to convince them, and to determine the point. 



" The earth, says the great Robert Boyle* harbours different kinds of petres- 

 cent liquors, and many of them impregnated with one sort of mineral or other." 

 There are no springs, no waters, but are more or less impregnated with such 

 mineral and saline particles ; which appears from the most limpid ; which, after 

 evaporation, still in the residuum, gives some particles of salt, with some stony 

 and mineral ones. 



Mr. S. has found by experience, that petrifying springs are generally impreg- 



* R. Boyle, of the Origin and Virtues of Gems. — Orig. 



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