Search -
Philosophical Experiments and Observations of Robert Hooke and Other Eminent Virtuoso's in His Time, Publ. by W. Derham
Philosophical Experiments and Observations of Robert Hooke and Other Eminent Virtuoso's in His Time Publ by W Derham Author:Robert Hooke General Books publication date: 2009 Original publication date: 1726 Notes: This is a black and white OCR reprint of the original. It has no illustrations and there may be typos or missing text. When you buy the General Books edition of this book you get free trial access to Million-Books.com where you can select from more than a million book... more »s for free. Excerpt: ) In the Minutes of the Royal Society, of Odob. 25, 1677, ijfW rf Experiment made that T)ay by 'Dr. Hook, which t for Congruity 1 Jhall infert here. T T was a very eafy Way to examine the com- I parative Weight of Liquors, and that to fo great a Nicenefs, as very fenfibly and manifeftly to exhibit fuch Weight of two Liquors, though they differ'd from one another, but a loooooth Part of their Weight. . This was performed by the Help of a large Glafs, of a Pear-Jike Form, equalling in Bulk a- bout three Pound of Water; which, by Shot included in it, was made almbft equiponderant toWater; but yet fomewhat heavier, that it might juft fink to the Bottom ; but by the fineft Hair, tied to the Stalk, could be fufpended in the Water. This Hair was tied to the Scale of a Beam ; and this Poife, by a Counterpoife in the other Scale, was made to fwim in the Water, fo as neither to touch the Bottom, nor the Top. And when fo poifed, it was found, that a 5th Part of a Grain added to, or taken from the Scale, would make the Glafs- Pear rife to the Top, or fink to the Bottom. Whence it was evident, that the whole Glafs, weighing about four Pounds (which amounts tcf 22040 Grains, or 220400 tenth Parts of Grains) and that one lingle tenth Part of a Grain would turn it. And the Glafs, when fufpended, being always equal to an equal Bulk of Water, if that Weight be alter'd a 2204001!! Part, the Pcife muft be alter'd, and confequently, by Help of the Scales, be made fenfible. This This Experiment, and the Nicety thereof being underftood by the Company, it was defir'd, that Trials might be made the next Day upon fe- veral...« less