Notices respecting- Netv Btoks. 149 



liodies had a tendency to gravitate, mutually, and to some 

 (•entre ; that they had a twofold force, one urging them to move 

 forward, in a straight line, the other downward, to a centre; 

 the two forces combined forming a curve : thus he accounted ior 

 the motion of the heavenly bodies, and all proceeded on mathe- 

 matical demonstrations, accompanied with the calculations of 

 algebra. 



" The other branches of philosophy, as well as astronomy, 

 were, in like manner, brought to the test of experience, and 

 subjected to mathematics and algebra. 



" Such was the philosophy of Newton. 



" The science which had been laid down by this great man in 

 the profoundest speculations, was opened in a more popular 

 manner by others, particularly by Whiston, as already observed, 

 in the public schools. — What has been said above upon this sub- 

 ject, has been delivered nearly in tlie Newtonian's own w-ords; 

 and it is not necessary to proceed further : suffice it that this 

 philosophy, made up, as we have said, of mathematics and 

 algebra, constitutes now the principal discipline, and prime 

 glory, of the University of Cambridge." 



Mr. Parkes, the author of " The Chemical Catechism," has 

 now in the press a Series of Chemical Essays, which he designs 

 to publish in four pocket volumes, including a variety of expla- 

 natory notes and a copious index. These Essays are" written in 

 a familiar style, so as to suit those readers who are not yet pro- 

 ficient in chemical science, and they embrace an assemblage of 

 curious and interesting subjects in 'the economy of nature, as 

 well as on some of the most important manufactures of this coun- 

 try. The work will be illustrated with more than twenty copper- 

 plate engravings, and all from original drawings, either of new 

 cliemical apparatus, or of such improved machinery as is now 

 employed in the respective manufactures on wliicli the author 

 has treated in these Essays. The whole is in considerable for- 

 wardness, and will })rol)abIy be ready for delivery by the end of 

 March or beginning of April. 



Mr. Accum has in the press " \ Treatise on Gas Light," ex- 

 hibiting a summary description of the apparatus and machiner)' 

 best calculated for illuminating houses, streets, and public edi- 

 fices, with ciirburctted hydrogen or coal gas ; togetiier with 

 remarks on the utility, safety, and general nature Of this new 

 branch of ci\il economy. This treatise will be illustrated with 

 geometrical and perspective designs, exhibiting the larger gas 

 light apparatus, now succcssfullv employed for lighting the streets 



K 3 and 



