Volume 1

Physico-theology; or, a demonstration of the being and attributes of God, from his works of creation. Being the substance of 16 sermons preached ... at ... Mr. Boyle's lectures in ... 1711 and 1712 / By the Rev. W. Derham... A New edition, with additional notes; a translation of the Latin and Greek quotations, and a life of the author.

  • Derham, W. (William), 1657-1735.
Date:
1798
Catalogue details

Licence: Public Domain Mark

Credit: Physico-theology; or, a demonstration of the being and attributes of God, from his works of creation. Being the substance of 16 sermons preached ... at ... Mr. Boyle's lectures in ... 1711 and 1712 / By the Rev. W. Derham... A New edition, with additional notes; a translation of the Latin and Greek quotations, and a life of the author. Source: Wellcome Collection.

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    B. IV. in a fiiort time (dd), in loud boatioiis; or to ex- prefs their thoughts near at hand with a gentle ' voice, them and fouthern parts, by the favour of my learned and illuf' trious friend fir Netiry Newton, her late majeily’s envoy at Flo- rence, I procured fome experiments to be made for me in Italy. His moft ferene highnefs the Great Duke was pleafed to order ^eat guns to be fired for this purpofe at Florence, and perfons were appointed on purpofe to obferve them at Leghorn, which they compute is no lefs than 55 miles in a ftralt line. But not- wlthftanding the country between being fomewhat hilly and woody, and the wind alfo was not favouring, only very calm and ilill, yet the found was plainly enough heard. And they tell me, that the Leghoi-n guns are often heard 66 miles off, at Porto Ferraro ; that when the French bombarded Genoa, they heard it near Leghorn, 90 miles diftant; and in the MeJJina infurreSion, the guns were heard from thence as far as Augujla and Syracufe, about joo Italian miles. Thefe diftances being fo confiderable, give me reafon to fufpeft, that founds fly as far, or nearly as far, in the fouthern, as in the northern parts of the world, notwith- ftandlng we have a few inftances of founds reaching farther diftances. As Dr. Hearn tells us of guns fired at Stockholm In 1685, that were heard 180 Engiyh miles. And in the Dutch war, 1672, the guns were heard above 200 miles. Vide Phil. *Tranf. No. 113. Alfo there is this farther reafon of fufpiclon, that the mercury In the barometer rifeth higher w'^hout than within the tropics, and the more northerly, fti .ne higher, which may Increafe the ftrength of founds, by note {ib). i^dd) As to the velocity of founds, by reafon the moft cele- brated authors differ about it, I made divers nice experiments jnyfelf, witli good Inftruments ; by which I found, i. That there is fome, although a fmall difference in the velocity of founds, with or againft the wind : which alfo is, 2. Augmented or diminifhed by the ftrength or weaknefs of the wind. But that nothing elfe doth accelerate or retard it, not the differences