30 INFSSTIGJTION of certain THEOREMS, &c. 



the fpberoid be infinitely fmall, or the triangle be very nearly 

 ifofceies. The application of the principle may therefore lead 

 into error, unlefs it be made with due attention to thefe re- 

 fbictions. The gentleman, juft named, will forgive a remark, 

 which J[ certainly mould not have made, if I had been lefs in- 

 terefted for the fuccefs of the work, in which he has aflifted with 

 fo much ability. 



II. 





