{6i p) Nnmk^. 
Beginning the Fourth Tear* 
PHILOSOPHICAL 
TRANSACTIONS. 
Monday, March 16. \66\ 
The Contents. 
An Introduction to the Fourth Year of thefe Tratts. An Account 
of the Invention of Grinding Oprick and Burning GlafTes of a 
' Figure not Spherically lately produced before the R. Society. 
Some obfervations by my of Anfmr to fome of the Inquiries con- 
cerning Tydesjropofed Numb.i 7. and 18. Queries and Diretti - 
ons for the Cmbz-l(lands. An Account of two Books : I SAG- 
GI Dl NATURALI ESPERIENZB fttte mlY ACA- 
DEMIA del CIMENTO, in FIRENZE A 1667. in 
Fol. II. VERA CIRCULI & HYPERBOLAE QUA- * 
DRATURA , in propria fua Proportions fpecie inven- 
ta & demonftrata a JACOBO GREGORIO Scoco , 
PAT A VII in 4 0 1667: Whence a Method is deduced of 
Meafuring the Area of an Hyperbole, and confcquently finding 
the Logarithrae*/ any Number, and e contra: And f his ap- 
flyed to ^Guaging or Menfuration of any Segment of any Cone, 
&c. ~ , 
An Introduction 
To the Fourth Tear of thefe Tra&s-. 
TN my Firft Number (of March, in the Yeir 166*5 0* rendered 
J[chc rsafons and purpofes of thzfcphilofofhical Communications ; 
la the Second Year fbc ginning in March A. 1666.U Numb.io.)\ 
enckavour'd to revive cn i imprefs the Utility of thefe United 
Corrcfpor dencies.Ia the T^/V^ye3r (beginning in March A 1667? 
Xxx at 
