Meteorological Observations at Sea. 87 



tions concerning the laws of atmospheric pressure, are com- 

 pelled in great measure to omit all reference to the obser- 

 vations which have been taken with them at sea. The fact 

 will, it is believed, afford a commentary upon the marine 

 barometers now in use, which no reasoning or explanation 

 can render more striking. 



" It was the opinion of the conference that it would not be 

 impossible, considering the spirit of invention and improve- 

 ment that is now abroad in the world, to contrive a ma- 

 rine barometer which might be sold at a moderate price, 

 that would fulfil all the conditions necessary to make it a 

 good and reliable instrument ; and a resolution was passed 

 to that effect, in order to call the attention of the public to 

 the importance of an invention which would furnish the na- 

 vigator with a marine barometer that at all times, and in all 

 weathers at sea, would afford the means of absolute and ac- 

 curate determinations. 



. " The conference is also of opinion that an anemometer, or 

 an instrument that will enable the navigator to measure the 

 force, velocity, and direction of the wind at sea, is another 

 desideratum. 



" The conference was of opinion, that the mercurial barome- 

 ter was the most proper to be used at sea for meteorological 

 purposes, and that the aneroid should not be substituted for 

 it. 



" With regard to thermometers, the conference does not 

 hesitate to say, that observations made with those instru- 

 ments, the errors of which are not known, are of little value ; 

 and it is therefore recommended, as a matter well worth the 

 attention of co-operators in this system of research, whether 

 some plan may not be adopted in different countries for sup- 

 plying navigators, as well in merchantmen as in men-of-war, 

 with thermometers the errors of which have been accurately 

 jdetermined. 



" For the purposes of meteorology various adaptations of 

 the thermometer have been recommended, such as those which 

 refer to hygrometry and solar radiation ; and, accordingly, 

 a space will be found in the columns for temperature by ther- 

 mometers with dry, wet, and coloured bulbs. With these ex- 



