Letters on philosophical subjects [electronic resource] : particularly the creation, the deluge, vegetation, &c. The powers producing these operations are here shewn to be heat, cold, air and water. Since the edition of these letters printed at Plymouth, the late experiments in the new chymistry have confirmed the above theory. These Experiments prove, that Heat and Light, together with Oxygen or Cold, are the Powers which carry on both Animal and Vegetable Life: Light, Heat, Vital Air, and inflammable Gas, are thereby proved to be substances of the first class, and approach nearest to simplicity.