Mechanical Philosophy). ii - 



forth discoveries and improvements, as the best 

 evidence of their utility. 



But astronomy has not only been enriched by 

 the augmentation of its own immediate revenues; 

 it has been also improved, during the period in 

 question, by the collateral aid of other sciences 

 and arts. The improvements in the mechanic artSy 

 by furnishing the astronomer with more perfect 

 instruments, have materially furthered him in his 

 course. The discoveries in dynamics and optics ^ 

 and the refinements which have taken place in ma- 

 thematical science, though apparently of small mo- 

 ment when considered in themselves, yet, when 

 applied to astronomical investigations, have proved 

 highly important and useful. Formerly astro- 

 nomy could only be improved through the medium 

 of actual observation; but when the great New- 

 tonian theory of the solar system was once estab- 

 lished, a new path of inquiry, and new grounds 

 of calculation, were laid down. Data, from that 

 period, were afforded for ascertaining, with great 

 precision, the orbits, the revolutions, and the in- 

 equalities of the several planetary bodies; and new 

 light and aid poured in on every side, from the 

 geometrician and the artist, as well as from the 

 immediate inquirer in this sublime science. 



Under this head it is proper to mention the in- 

 troduction of the New or Gregorian Style of chro- 

 nology into Great-Britain in 1752. In 1582 

 Pope Gregory XIII. finding perplexity to arise 

 in the computation of time, from some errors in 

 the Julian Kaleiidar, which, antecedently to that 

 period, had been used throughout Christendom, 

 thought proper to order the formation and adop- 

 tion of a new style of reckoning. The astronomers 

 and mathematicians whom he summoned to Rome 

 for that purpose, after spending several years in 

 investigating the subject, and adjusting the prin- 



