Fontenelle, of the Vfefulnefs 



Altho' the Ufefulnefs of Mathematicks and Na- 

 tural Philofbphy is obfcure, yet it is real. To 

 confider Mankind in their Natural State, nothing 

 is more ufeful to them, than what may prefer ve 

 their Lives, and produce thole Arts, which are 

 both great Helps and Ornaments to Publick So- 

 cieties. 



As for what concerns the Prefervation of Life, 

 it peculiarly belongs to Phyfick ; which for that 

 rea(bn is divided in the Academy into three 

 Branches, which make three different forts of 

 Members of this Society, Anatomy, Chymiftry, 

 and Botanicks. Every Body knows of what Im- 

 portance it is to have an exacl: Knowledge of Hu- 

 man Body, and of what Medicines may be extra- 

 £ted from Minerals and Plants. . 



As for Arts, too tedious to be reckon'd, they 

 depend fbme upon Natural Philofbphy , others 

 upon Mathematicks. 



One wou'd think at firft, that if the Mathema- 

 ticks were to be confin'd to what is ufeful in them, 

 they ought only to be improv'd in thofe things, 

 which have an immediate and fenfible affinity 

 with Arts, and the reft ought to be negk6ted as 

 a Vain Theory. But this wou'd be a very wrong 

 Notion. As for Inftance, the Art of Navigation 

 hath a necelfary Connexion with Aftronomy, and 

 Aftronomy can never be too* much improvM for 

 the Benefit of Navigation. Aftronomy cannot 

 be without Opticks by reafbn of Perfpe&ive 

 Glaffes ; and both, as all other Parts of Mathe- 

 maticks, are grounded upon Geometry, and to go 

 as far as you can, even upon Algebra. 



Geometry 



