CONTENTS. 



Marquis of Woiccfter's defcrJpuon— Savery's engfne. Hiftory and adjuftment of the claims of the 

 Marquis of Worceller and Savery as to the invention of the fteam engine. Papin's fleam engine. 

 The engine with a pifton. Comparifon of Savery's and Newcomen's engines. Kcir's engine on 

 Savery's principle. Defcription. Peculiarities. Steam engine with lifts. 



V]I. On the Mechaniftn by which the Mariner's Compafs is fufpended p. 426 



Introduflion. Sufpenfion of the magnetic needle on a cap— requifites for fteadinefs. Compafs-box 

 fupportedon a point— or by gimbals. Adjuftment of the gimbals for fteadinefs. Eafy trial of » 

 good compafs. Lorimer's fufpenfion of the dipping needle by gimbals. 



VIII. On the maintaining Power in Clocks and Watches — p. 429 



Vibrations of pendulous bodies — ^Train of wheels. 



Mathetnatical and Philofophical Correfpondencc p. 430 



Optical queftion concerning the glory in water anfwered. Vifible emanation from reftified animal oil. 

 Anfwcrs to mathematical queftions. 



Vol. J.— March 1798.— SufPL. .. JANUARY 



