144j Hourly Meteorological Observations. 



gressive increase between the equator and the latitude of Cu- 

 mana." 



Paeis, September 1826. 



Aut. XX. — 'Notice respecting the hourly Meteorological Ob- 

 servations proposed by the Royal Society of Edinburgh, to 

 be made twice every year, on the 17th July and 15th Ja- 

 nuary. 



In obedience to the request of several correspondents, we pro- 

 pose, in the present notice, to explain more fully than was done 

 in the printed schedules, the method of making the meteorolo- 

 gical observations proposed by the Royal Society of Edin- 

 burgh, and to subjoin a copy of one of the sets of observations 

 made on the Ifoh July 1826. 



the days of the year which have been fixed for these ob- 

 servations are the 17th July and 15th January, and it would 

 be extremely desirable to have these observations repeated on 

 the same days of these months for some years. 



1. The first column of the schedule is intended for register- 

 ing the state of the thermometer every hour of the day, from 

 1 o'clock a. m. to 12 p. m. of the 17th July, or the 15th Ja- 

 nuary. The thermometer should be placed in a northern ex- 

 posure, sheltered from the direct rays of the sun, and at some 

 height above the ground. The times of the highest and lowest 

 state of the thermometer should also be marked, if they do not 

 occur at any of the hours of observation. 



2. The second column is intended for registering the tem- 

 perature of springs and deep wells, or tjie temperature of a 

 river, or of the sea. 



8. In order to obtain the force of radiation, a mercurial 

 thermometer, having its bulb covered with black woollen cloth, 

 or simply blackened with China ink, should be exposed on an 

 open spot of ground, and a few folds of paper may be inter- 

 posed betwen the soil and the instrument. The same result 

 will be obtained by taking the temperature of an exposed patch 

 of bare soil. 



4. The barometer or sympiesometer, whose indications are to 



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