long with them ſuch light bodies as they meet with in their way. On occaſion of which Hypotheſis I ſhall offer it to be conſider'd, Whether by the gravity of the Atmoſpherical Air, ſurmounting the Specifick Gravity of the little and rarifi'd Atmoſphere, made about the Amber by its emiſſions, and compriſing the light Body faſten'd on by them, the Attraction may not in divers caſes be either cauſed or promoted.
Another Hypotheſis is that propoſed by that Ingenious Gentleman Sir Kenelm Digby, and embraced by the very Learned Dr. Browne, (who ſeems to make our Gilbert himſelf to have been of it) and divers other ſagacious men. And according to this Hypotheſis, the Amber, or other Electrick, being chaf'd or heated, is made to emit certain Rayes or Files of unctuous Steams, which, when they come to be a little cool'd by the external air, are ſomewhat condens'd, and having loſt of their former agitation, ſhrink back to the
body
