coftftant Circulation, is driven and feorn upwards ^ 
wherefore fuch places prove barren. On the other hand, 
thofe places which do embrace water like a fpunge, as the 
marfli lands do, thefe grow warm, and makeahnoftan 
infeparable union, with the fait contained in the water^- 
which makes that land very fruitfull. So that I cannot 
but believe, that there muft be two contrary falts in I{fgna 
Ve^etabili ^ Animali,t]i2it contrarys are neceffarily found 
in bodysfolubIe,and combuftible, which overthrows the 
Maxim : Contraria in um Corpore non^ 5cc. Again, in fome 
meafure tis true, contraria inter fe pugnare ^ when by 
Motion, they are brought to a difpropertion : but, when 
by nature, or Art, they are brought to contain true pro- 
portions, this proverb hath an end. Thus heat and cold, 
when one much prevails over the other^ produce Thun- 
der, and Lightning. But of this notion, I hope another 
time, to give a farther explication. I fliall only fpeak 
a word, to the opinion of thofe, that think Thunder, 
& Lightning, proceeds from Sulphur, becaufe they have 
found it to rain Brimftone ; which is nothing elfe, but 
the yellow duft, to be found in the blolToms of the Fir 
Tree, and of the Pine Tree , and alfo of the Hazel , 
blown off, and carryed by the Winds into the Air, which 
is again thrown down upon the ground,by Violent tlorms 
of rain : upon the examination of this powder, they 
may foon find it no Brimftone. Others are carryed into 
this error, that heat, and flame, muft needs proceed 
from oy 1 : but we muft leave them in their meaning, be- 
caufe thefe imagine , they have hit upon fome new thing. 
All new matters, if they have but a foundation of truth, 
are good, or bad, as they are made ufe of. 
That I may not in an affair, wherein perhaps, you 
have made much better Obfervations, too long detain 
you, I Ihall only feleit an Obfervation, or two, wherein 
I have particularly obferved, that a Calidum i3 Frigidumy 
are to be found in a Fulminating,and combuftible body. 
I fliall alfo be glad to h% informed oi the contrary by any 
M Chymift 
