372 Astronomical and Magnctical Observations. [Mat, 



has been obtained by all the valuable discoveries that have enriched 

 the science of chemistry of late years. 



These observations are intended, with much deference, merely as 

 hints, or rather as the crude reflections naturally flowing from an 

 early consideration of the subject. To others far more competent 

 must be left the prosecution of this important task. As yet, how- 

 ever, it is too early a period for speculation ; our knowledge is not 

 sufficiently expanded to enter too far into the ordinances of the 

 universe. VVe have only steadily to pursue the course so success- 

 fully led by the many great men of the present day, especially that 

 so admirably marked out by your exertions, and by aiming at those 

 objects only within our reach, we cannot fail of making gradual 

 but rapid advancements to the objects of our exertions. 



To conclude, I have only to regret that my professional avoca- 

 tions allow me but little opportunity of making much progress in 

 my researclies ; what little leisure I can spare shall be most 

 earnestly devoted to this favourite object ; and as soon as 1 can 

 collect materials sufficiently worthy of your observations, I will 

 immediately transmit you the results of my humble efforts. 

 1 am. Sir, with the most profound respect, 



Your obedient servant, 



HI, strand, Feb. 12, 1814. ' JoHN MiERS. 



Article VII. 



Astronomical and Magnetical Observations at Hackney IFick, 



By Col. Beaufoy. 



(To Dr. Thomson.) 



MY DEAR SIR, Hackney Wick, April IT, 1814. 



I HAVE the pleasure to send you the magnetical observations 

 which will complete the twelve months' series, as well as the com- 

 mencement of the second year's. 1 have only to remark, that every 

 observation was made by myself, and that the most scrupulous 

 attention has been paid to the subject. Fourteen observations were 

 generally made with each needle, in the following manner : seven 

 readings off from the instrument were set down, the needle was 

 then drawn by applying a key or other piece of iron ; and when the 

 needle was settled seven more readings off were set down, and the 

 mean of the fourteen observations was considered as the true varia- 

 tion of one of the needles. The experimented needle was then 

 removed, and another placed in the box of the instrument, and 

 fourteen observations were made in a similar manner ; the mean of 

 both needles was considered as the true variation. It may be 

 proper to remark that needle number four weighs 48 grains, and 

 needle number five Co^j and that the former points out more 



