( 104 ) 
hold each 25 or go pounds, and thefe theyexpofe to clear 
Nights 5 and if there be apy impurity remaining, it Will fall 
to the bottom : Afterwards they break the Pots, and dry 
the Salt in the Sun. One might make vaft quantities of Salt- 
pet re in thefe parts *, but the Country People feei g that We 
buy of it, and that the Englijh begin to do the fame, they 
now fell us a Maon of 6 pounds for two Rupias and a half, 
which we had formerly for half that price. 
An Account of Hevelius bis Prodromus Cometicus 5 
together with feme Animadverfions made upon 
it by a French Philofopher. 
This excellent D anii f can Aftronomer, Heveliu /, in his Pr<?» 
drowns (by him fo call’d, becaufe it is as a Harbinger to his 
Cometography , which hath already (b far pa (led the Prefs, 
that of twelve Books there are but three remaining to be 
Printed) gives an Account of the Obfervations he hath 
made of the Fir/i of the two late Comets 5 referving thofe 
hehaih made of th efecond, for that great Treatife, where 
he alfo intends to deliver the Matter of this flrft more parti- 
cularly and more fully then he hath done here. 
In this Account he reprefents the Rife, Place, Courfe, 
Swiftnefs, Faces and Train of this Comet, interweaving 
his Conceptions both about the Region of Comets in gene- 
ral (whether it be the Air 9 or the JEtber .<?) and theGaufes 
of their Generation : In the fearchof which latter, he in- 
timates to have received much affiftance from his Tehfrope. 
Heobferved this Comet not before Oecemb . (though he 
conceives it might have been feen fince Novew. & he 
fjw it no longer then Febr . A ; though feveral others have 
feen it both fooner, and later : and though himf ’f continu- 
ed to look out for it till March y.Ji. n» but fruitlefly, where- 
of he thinks thereafon to have been its too great diftance 
and tenuity. 
He 
