C ) 
Fermentations of Natural things are caufed hence, that thefaid 
Nitro-aerial particles, penetrating the Salino-falphureous 
mafs, do enter into the body of the Subtile matter^ by which, 
beingpiu in a great agitation, chefaid Nitro-aerial pares are 
.protruded together with theSulphureous ones;fo that theEfFer- 
vefcence of Fire feems to him to differ fi cm the more remifs 
Inteftin motions, by which Vegetables are generated or diffol- 
ved, only in this; that in Fire the Nitro-aena! particles being 
clofely joyned with the Fixed Salt or parts of the Air, arc 
by the impuife of the Suiphureous parts and the fubril matter 
carried away with violence , and put into a very fwift agita- 
tion ; whereas in other Fermenraxions , the Suiphureous parts 
not being 'odged fo faft in the embraces of the Fixed Salt, are 
by the pulfation of the Nitro-aerial parts and of the w^^m^ 
moved with more remifTenefs, 
Having difpatch't this argument,he maketh an excurfion in- 
to the Ocean, and labours to give an account of that Afcent of 
the waters in the Sea, which is commonly call'da Sput \ deduc- 
ing it from a vehement r<?m^<? or whirling of the Air: of the 
particulars whereof himfelf may be confuited, 
iVm.hc difcourfes of luight and Colours , embracing the 
dofirine of Des^Cartes^ making hight to confiftina pulfe, 
which by reafon of the continuity of the luminous Medium is 
fuddenly tranfmitted to the greater diftance ; but this Impuife 
our Author would have made by his Nitro-aerial particles ; as 
he is of opinion,that Colours dX^ produced not from a light re- 
fleaed,but from a peculiar impuife of the medium^ altogether 
different from that of Light ; concerning which and the man- 
ner of which, the difcourfe it felf may 1 ikewife be perufed^ 
To this he fubjoyns a Chapter about Light nmgy^\\ic\\ he de- 
nies to proceed fiom kindled exhalations ; and having efpou- 
fed the C^rtejtan opmiox\oi the produflion of Thunder from 
the impetuous fall of the upper condenfed and conglaciated 
clouds upon the lower^he thence infers,that Lightning is made 
by his Nitro-aerial particles ftruck out of the Air , and by 
their vehement igneous motion caufing a flight and momeritane- 
ous flafhfpreadingit felf over the whple Hemiiphere. Where 
he adds his thoughts about the force of Lightning, and its won- 
: derful 
