Oji the Path of the " Boomarang:' 329 



force of the several reasons by which I may have been influ- 

 enced in doing so*. 

 Durham, September 1837. 



Note, — It may be in the recollection of many of the readers 

 of this Journal, that Dr. Clarke of Aberdeen, in a letter to 

 Professor Mitscherlich published in the Records of Science, 

 endeavoured to show that the atoms of one or more of the 

 alkaline metals should be doubled; in a subsequent paper 

 I propose to consider the principle on which his reasoning is 

 founded. 



LIl. On the Path of the projectile Weapon of the Native 

 Australians called the " Boomaran^^ or " Kylee." By a 



CoRRESPON DENT, t 



To the Editors of the Philosophical Magazine aiid Journal, 

 Gentlemen, 



A SHORT time since my attention was directed to the 

 " Boomaran^^ or " Kylee^^ known for a considerable time 

 to the scientific world, and at present become a very general 

 source of exercise and amusement. You must be aware that 

 when thrown in a certain direction, it will return to, and 

 sometimes far beyond, the spot from which it was projected. 

 Curiosity induced me to devote some attention to the subject ; 

 and unable to see any insufficiency in the following simple 

 causes, by which I have endeavoured to account for this 

 curious property, 1 am surprised that none of your learned 

 correspondents has favoured the public with any explanation 

 of it. Should the following observations appear worthy of 

 the attention of your readers, I am sure you will not refuse 

 them an early insertion in your excellent Journal. 



I. To explain the principles on which the kylee ascends, 

 and afterwards returns to the place from which it was pro- 

 jected, it will be necessary to consider the various forces 

 which act on it, from the time it is projected until its return 

 to the earth. These forces appear to me to be five: first, 

 that of projection ; secondly, that of gravity ; thirdly, the re- 

 sistance of the air to its plane or level side ; fourthly, that re- 

 sistence to its curved side ; and fifthly, to its edge. The last 

 three forces, though distinct in their effects, are but one in 

 their nature or cause. In enumerating these forces, I have 

 supposed your readers to be perfectly acquainted with the 

 form or shape of the body. Let us now examine the effect 



[* How will this subject be affected by the application of the mode of 

 determining true atomic weights pointed out by Mr. Faraday, in his 

 {Seventh Series, par. 851 ; or L. and E. Phil. Majr., vol. v. p. 430? Edit.] 



t A notice of a paper on the Boomarang will be found in our report 

 of the Royal Irish Academy's Proceedings in a future page. 



