Q,4f SCIENTIFIC NEWS. 



On Phofphoric Rings; from a Correfpondenl : R. B. 



Phofphoric ^ DO oot know that any one has explained the phenomenoiii 



i'^^&i' of thofe denfe cloudy rings which are produced when phofpho- 



rated hydrogen ariCes through water, and explodes in the air ; 

 an efFedl fimilar to what is fomelimes (een on the tiring of can- 

 non. Upon clofe infpedion the faft appears to take place thus. 

 The bubble of hydrogen, containing phofphorus in folution, 

 rifes and takes fire. Phofphoric acid is feparated in the form 

 of white fmoke; through which denfe mafs the expanfive ac- 

 tion is directed upwards. A fluid opaque ring, denfer than the 

 atmofphere is thus fornied, the inner furface of which is made 

 to afcend by the rapid ftroke, while the external part has re- 

 ceived little or no impulfe. The natural confequence is a quick 

 rotation of the ring, from within outwards, which fliews itfelf 

 to the fight, and feems, in fome manner or another, as if it 

 kept the parts together. 



Ilotv to jneafare the Contents of any Pipe by a very readj/ Method, 



Co:>tents of any MY ingenious correfpondent, Mr. Woolf, fometime ago 



pip; in pounds gave me a ready method of meafuring the contents of a pipe, 

 01 gallons. « ^ „ ^ ^ ^ ^ 



as loliows: 



Square the diameter in inches, and the produfl will be the 



number of pounds of water in every yard length of the pipe. 



Or if the laft figure be cut off or confidered as a decimal, the 



vemuii5ing figures ^^•ill give the ale gallons in the yard. 



