20 Sketch of Bristol. 



lour is produced. On standing a short time, a pre- 

 cipitate takes place, having a yellow appearance. 



Here I intend not to speculate. I shall, however, 

 add a conjecture, and beg it may be regarded as 

 such : That where the town now stands has been 

 made ground, and within no great period of time. 

 How, if at all, this was effected, I pretend not to say. 

 The fact which suggested the idea is the following, 

 and came within my own knowledge. At the depth 

 of about twenty-five feet below the surface, the earth 

 is found to be the same as that of the adjacent marsh, 

 to wit, a black mud, both which must be nearly 

 upon a level. At this depth, in several places, have 

 been found large sticks, or rather logs, of wood, sound 

 and uninjured by the waste of time, except perhaps 

 one fourth of an inch on the surface. I am not 

 satisfied what kind of wood it was. It was something 

 like pine. 



Diseases are, no doubt, influenced by soil and si- 

 tuation. To the neighbouring marshes, together with 

 the fogs, which we have during several months in the 

 fall, have been ascribed the intermitting and remit- 

 ting fevers which are epidemic every season. I am 

 informed, that thirty years since, the former of these 

 diseases was much more prevalent than at present, 

 and yielded to the bark and other tonics, with less 

 evacuations. And yet, my preceptor, Dr. Gregg, is 

 of opinion, that winter diseases were more acute, and 

 bore the debilitating plan better than they do now. 

 'The disease was ascribed, at that time, to the break- 



