Sy6 JAMAICA. 



ctit pan fugar, which is the hard crufl formed about the mouth of 

 the iacbe, and which cannot well be taken off" without fcraping at 

 the fame time into the very fubftance of the lead, do not fufi^er any 

 of thofe fpalmodic fymptoms in their bowels after eating it, which 

 the ruft or effluvia of this metal are apt to caufe, when combined 

 with things which are not qualified to correal their natural effcds. 

 Dr. Cremer obferved, that the potters at Ofterhout near Breda, 

 though conftantly employed in glazing earthen veffels, were rarely 

 affeded with any diforder in their bowels ; which exemption he 

 attributes to the large quantities of butter and fat bacon, which are 

 their ordinary food ; fo experience has taught the labourers in lead 

 jnines, to fortify their ftomach, and inteftines, with fat broths, and 

 llich like un3:uous aliments, which are antidotes to this poifon. 



The vapour arifing from the fmelted ore at the mines in Mendip 

 Hill?, in Somerfctfhire, is fo poifonous, that if it fweeps the ground 

 adjacent, it afteds the grafs in fuch a manner, as to deftroy cattle 

 or iheep that browze on it- There is ?l fight, or light fubffance, 

 which floats in the Iraoak; and this, if it chances to mix with the 

 water in which the ore is waflied, and carried away with the ftream, 

 is faid to have deffroyed cattle, that have drunk of it after a current 

 •of tluee miles. 



The diforders to which the workmen are fubjeft, are pains in the 

 ftomach, violent contorfions of the bowels, obflinate coftivenefs, 

 afihmas, and fhortnefs of breath, vcrtigos, paralytic affedions, 

 lofs of appetite, licknefs, and frequent vomitings. 



The foil about thefe mines is red and ftoney; and the ftones 

 wafhed by the brooks and fprings, are of a reddifli cafl and very 

 ponderous : I cannot precifely anfwcr, whether the foil about the 

 Liquanea lead mines has a conformity in this refpect. It feems, 

 fiom the foregoing account, that a ftrong degree of heat is required 

 to difengage this pernicious fume j the fubterraneous heat is fufficient 

 for fuch an effecl in fome places, where there ^xejirata of particles 

 qualified to produce it by their fermentative adion. No doubt too, 

 but flones containing this mineral, if lying upon and very near the 

 furface expofed to a Tropical fun, may caufe this poifonous vapour to 

 be emitted or perfpired in fome degree; and, mixing with the air, 

 may render it unwholefome; but we have no certain proof, that 

 2 ^^^y 



