Account of some Meteorological Instruments. 



uses to which it may be applied. In the gas-works it would be a much more 

 delicate indicator of the progress of the operations than the pressure gauge 

 usually employed there. 



In its general construction it resembles that of the floating gas-holder; but 

 it differs from it in this particular, that the elasticity of the air in the gas- 

 holder is kept as nearly as possible the same, whatever quantity may be in- 

 side ; while in Mr Adie's instrument, the load is regularly increased with the 

 elevation of the instrument, so that that elevation becomes a measure of the 

 excess of the elasticity of the included air over that of the atmosphere, or of 

 the difference of level between the outer and inner fluid. 



From a minute examination of a beautiful specimen of the instrument in 

 Mr Adie's own possession at Liverpool, one of your Committee is quite satis- 

 fied that the construction is susceptible of great precision and of extreme de_ 

 licacy. 



Your Committee, therefore, gladly recommend this instrument to the fa- 

 vourable notice of the Society. EDWARD SANG. 



JAMES TOD. 



Edinburgh, IVth November 1836. 



Account of some Meteorological Instruments. (With a Plate.) 



THE importance of obtaining simple Meteorological In- 

 struments, which are capable of indicating the maxima and 

 minima of atmospheric changes, during the absence of the 

 observer, has always been acknowledged. The following de- 

 scriptions of three instruments of this kind, contrived by Pro- 

 fessor Traill, have not, we believe, yet appeared in an English 

 publication, though they were exhibited and explained by him 

 several years ago, when he lectured in the public institutions of 

 Liverpool, and though he read a short description of them to the 

 meeting of German Philosophers at Hamburg, in 1830 ; as ap- 

 pears by the account which Oken has given in the Isis for 183L 

 The instruments are simple in their principle, and seem well 

 suited for the intended purpose. 



I. Register Anemoscope. The indications of the direction of the winds are 

 generally given in a very imperfect manner in meteorological journals ; it is 

 rare to find more than a single point of the compass noted for each day ; and 

 even this is seldom given with tolerable precision. It is obvious, however, 

 that If we hope ever to arrive at any knowledge of the causes that influence 

 the direction of local winds, it must be founded on more accurate means of 



