540 PHILOSOPHICAL TRANSACTIONS. [anNO l6g3. 



shorter : and discoursing since with a certain commander upon this subject, he 

 told me he was once present when upon a wager a cannon of 14 feet threw a 

 ball much farther than one of 18 feet.* 



As to the reason, how so great a quantity of air comes to be generated, 

 though I thought of several solutions, yet I could not satisfy myself; I some- 

 times thought that the particles of the air were by the violent motion broken 

 and comminuted into smaller, and so between each particle a much finer sub- 

 stance might be placed, but this did not answer so great an expansion. Upon 

 the whole, I concluded that the greatest improvement that can be made in 

 shooting, is, if possible, so to order the matter, that all, or the greatest part of 

 the powder be fired at once ; and when this is effected, a much less quantity 

 will serve than is now used. 



To examine yet further this matter of new-made air, I took one grain weight 

 of crabs' eyes, to which I poured wine vinegar, and in 4 hours as much air was 

 generated as filled the space of 44 grains of water; and 3 grains of crabs' eyes 

 produced about 3 times as much. This new-made air kept its expansion for 12 

 hours that I observed it, whence it appears to have been true air. 



Description of the American Tomineitis, or Humming Bird, communicated by 

 Nehemiah Grew, M.D. and F.R.S. N° 200, p. 76G. 

 There is nothing, in this paper that can justify reprinting it, nor is it possible, 

 from the description given, to determine the particular species meant by the 

 writer. 



An Account of Boohs, viz.— I. Horti Indict Malabarici. Pars Septima, Octava, 

 et Nona ; with some Remarks upon them. N° 200, p. 762. 



The first 6 tomes being abbreviated in the Philosophical Trans. N° 145, and 

 N° 198 ; this proceeds with the 7th, 8th and Qth, the productions of the noble 

 Hear Van Rheede. The 7th part treats of scandent and bacciferous shrubs, 

 the greatest part never before noticed or but very imperfectly : as the natsjatam 

 or battavalli, which is the cocculijs indicus of our shops, used in ointments or 

 pastes for intoxicating fish, and driving away lice and vermin. It is an ever- 

 green, and grows in sandy places : the leaves are thick-set, of the shape of a 

 heart, and of a bitter taste. The flowers come out in clusters; are monopeta- 

 lous, with five laciniae or incisures, all reflected, like those of the night-shade, 



* Mr. L. seems to have mistaken the cause of this effect, even if this were generally true, which 

 is not the case. The cause might probably be in the powder ; but may sometimes by accident pro- 

 duce the effect, by some friction or resistance within the bore of the gun, as well as other causes 

 from the irregular fligh of cannon balls. 



