346 Miscellaneous Intelligence. 



the more accurate culture of grain than is generally adopted in 

 this country. 



3. New Stop-Cock for Piieumatic Apparatus. — Inconsequence 

 of the frequent imperfection of the common stop-cock for the 

 retention of condensed atmosphere, Sig. Crivelli, Professor of 

 Natural Philosophy at Milan, has invented another, which is 

 supposed to be free from the objections that may be made to the 

 first. The annexed diagram will explain its construction. 



It consists of a box a, and plug b, both of the usual form : 

 also a conical valve c, and a spring tube d. The aperture 

 in the end of the stop-cock, from e to y is conical, and care- 

 fully ground. The other part inwards is cylindrical ; the valve 

 is a metal rod extending from c to g, and made conical in the 

 part corresponding to the aperture just now described, so as to 

 fit it with great accuracy. This valve is retained in its place 

 in a shut position by a small spiral spring in the tube d, which 

 tube screws on to the worm e. The side of the box correspond- 

 ing to the other aperture h, has no appendage, but is finished 

 by having a groove cut in its inside, nearly half way round i, 

 and level with the valve and the aperture. The plug of the cock 

 is not bored, but has a groove cut in it, k, deepest in the middle 



