486 



The author verified, both at Liverpool and at London, the exist- 

 ence of a fact similar to that which M. Daussy had ascertained at 

 Brest, namely, the rise of the ocean when the barometer is depressed; 

 and remarks that the correction due to changes in the atmospheric 

 pressure is by no means inconsiderable. He suggests the question 

 whether the surface of the ocean rises in narrow seas simultaneously 

 with the depression of the barometer, or otherwise. With a view to 

 the solution of this question, he gives a tabular diagram showing the 

 correspondence between the calculated and the observed heights, in 

 their relation to the heights of the barometer at Liverpool and at 

 London, from which it would appear that the effect of changes in the 

 atmospheric pressure on the tide is immediate. 



" On an improved mode of constructing Magnets." By James 

 Cunningham, Esq., Member of the Cork Scientific and Literary So- 

 ciety. Communicated by North Ludlow Beamish, Esq , RR.S., 

 President of that Society. 



The material recommended by the author for the most economical, 

 as well as effectual method of constructing magnets, is cast iron, 

 which should be formed in small castings in the form of a horse-shoe, 

 each weighing about seven ounces ; these he finds, on being touched 

 in the usual manner by a small compound magnet, received and re- 

 tained the impregnation better than any which he had previously 

 constructed of steel. 



The Society then adjourned over the long vacation, to meet again 

 on the 16th of November next. 



