(894)
Wars, and the horrible Conflagration of our Metropolis; yet we then made an Attempt of laying some Foundation for the Improvement of real Philosophy, and for the spreading of Useful knowledge; in publishing Advices and Directions for the writing of an Experimental Natural History; in pointing out Essays, Patterns and Exemplars, that have hitherto been designed in that kind; in giving notice of divers Artificial Engines and Instruments, which may be helpful for the further Discoveries of Nature, or for the greater performances of Art. We ought out, how far Art had then arriv'd towards the perfecting of the Microscope; and by what means that curious Instrument might be advanc'd; and what Informations it would afford us, either upon the view of minutest Bodies; or of the Texture, Surface, Porosities, Smoothness or Inequalities of other Bodies, that were in our power for such approaches. The like care we had for Telescopes, by what Operations, Engine, and Applications they might he further improv'd; and what was the most, they could thus far perform. Then we related the Finding out of the Rotation of some of the Planets, and the Changeableness, and Seasons of absence, or Obscurity in some of the Fixt Stars, or such as seem'd to he of their Train, And never, I think, were Comets so chaced, their Figures and Appearances so detected, their Motions almost reduced to Rule, and in a manner predicted; the Solar Eclipse in several and distant places carefully calculated. And not to recite here, what was attempted and done by Burning-Glasses; I shall but name the Instruments devis'd to Measure the Weight and the Changes of Weight of the Air, and other ascending and descending Fluids, either with the Pressure of the whole Atmosphere, or of smaller parcels freed from that Pressure; I mean the Baroscopes, and the Pneumatick Engins, There were also offred Hygroscopes, to note the degrees of Drought or Moisture in the Air; Thermometers to measure the degrees of Heat and Cold; and an Instrument to graduate Thermometers to make them Standards of Heat and Cold; an Instrument to measure the Refractions of Liquors of all kinds, for establishing the Laws of Refraction; Hydrostaticks to measure the Weight of Liquids, and divers other Contrivances to find out the Statical position, tendency and gravitation of Liquids in all parts. Besides, Engins to break the hardest Rocks; Huge Wheels and other Engins for Mines described; To raise Winds, by the fall
