388 PHILOSOPHICAL TRANSACTIONS. [aNNO iG//. 



An. 1675, July 12. — The new star in the Swan's breast shines again at 

 nights, but only as a star of the sixth magnitude. 



An. 1676, Dec. 10. — I well remember that I could not see the new 

 star in Collo Ceti> though I observed many small stars in the same part of 

 the heavens. 



Dec. 23. — ^The sky being very clear, we saw very plainly the new star in 

 the neck of the whale. It shone with such brightness and was so large, that 

 it not only equalled, but even exceeded that in the Whale's jaw. 



Dec. 31. It was again observed larger than that in the jaw, that is, of the 

 second magnitude. 



An. 1677. — Jan. 1. It again shone out very brightly, rather larger than 

 the star in the jaw, than that in the extremity of the wing of Pegasus and 

 Marcab, in colour and light not unlike to the jaw. Yet I remember to have 

 formerly observed, when it was of the second magnitude, that it was rather 

 whiter and brighter. 



^n Account of two Books. N° 134, p. SSQ. 



I. Traite de la Percussion ou Choc des Corps, &c. par Monsieur Mariotte, 

 de I'Academie Royale des Sciences. A Par. 1673, m \1^. 



In this work are treated the effects resulting from the shock of bodies, both 

 clastic and non-elastic: in which the author confirms the reasonings of some 

 preceding philosophers, and delivers some new ones of his own. 



From several reasons and experiments by him delivered, he concludes, that 

 the greatest part of hard bodies, as steel, marble, glass, ivory, jasper, &c. have 

 a ready and strong springy power ; and that all the motions of reflecting bodies 

 are only made by springs. Whereunto he adds, that if it should be supposed 

 that hard bodies are inflexible, it would be impossible to explain their motions 

 when their weights are unequal, and that the phaenomena do no ways agree to 

 such an hypothesis. But taking it for a mere hypothesis, what he pretends to 

 have demonstrated concerning the springiness of hard bodies, he tells us, that 

 by that means all motions befalling those bodies, after they have any way im- 

 pelled one another, may easily be accounted for. 



II. Johannis Trithemii Steganographia, vindicata, reserata, et illustrata, &c. 

 Auth. Wolfgango Ernesto Heidel, Wormatiensi. Mogun. 1676, in4to. 



This Steganography, or the art of signifying ones mind to another by an 

 occult or secret way of writing, having been censured as supposititious by some, 

 and pernicious, magical and necromantical by others ; this author undertakes to 

 vindicate it from those imputations, and to give the true key and meaning 

 thereof. 



