ON MAGNETI CAL AND METEOROLOGICAL OBSERVATIONS. 3 
going hand in hand with theory, would act as a powerful engine of public 
instruction. 
Magnetic Surveys. 
The completion of Lieut. Lefroy’s North American Survey has furnished 
data in the highest degree satisfactory. Above 100 stations have been ob- 
served by him, at which the three elements have been determined within the 
isodynamic oval of 1°7 in North America. The examination which has been 
instituted of these shows the observations to be satisfactory. His magnetome- 
trie observations, made hourly during the winter, show some extraordinary 
disturbances; one on the 17th April 1844, gave changes of 8° 10’ in declina- 
tion and 0°16 of horizontal force. 
Lieuts. Moor and Clerk sailed on the 9th of January from the Cape, on 
the magnetic survey of that portion of the Antarctic Ocean left unexplored 
by Sir James Ross, to which allusion was made as contemplated in our last 
report. This survey will complete our knowledge of iso-magnetic lines in the 
South Seas. 
In the United States Prof. Renwick has occupied himself with the obser- 
vation of the three magnetic elements at the stations of the Trigonometrical 
Survey from Rhode Island southward to Annapolis in Maryland, while Prof. 
Bache carries on the same process from Annapolis southward, and in the 
course of the current year will probably have extended his operations to the 
Gulf of Mexico. The former of these zealous cooperators in our cause has 
proposed to establish, at Columbia College, a barometrical record simultaneous 
with that at Toronto, in which instruments carefully compared with our 
standards, by means of a portable barometer making the circuit of London, 
New York, Toronto, New York, and London, will be employed. 
Publication of Magnetic and Meteorological Observations. 
The Toronto observations of 1840, 1841 and 1842, are printed, and in the 
hands of most of our correspondents. So are also the first volume of ‘ Extra- 
ordinary Magnetic Disturbances at the Government. Stations,’ and two vo- 
lumes of the ‘ Greenwich Observations,’ containing those of 1840, 1841 and 
1842. An immense arrear remains, and must remain, in spite of every exer- 
tion, unless an increase in the superintendent’s establishment afford the means 
of greater despatch. Representations have been made with the view of pro- 
euring such increase, the result of which is not yet known. Should it prove, 
as it is hoped, successful, the work of reduction and publication will proceed 
with all desirable alacrity, and the world be speedily put in possession of the 
whole results. 
_ The Honourable the Court of Directors of the East India Company has 
_ been applied to on the part of the Royal Society, to authorize the printing of 
_ the observations communicated from the four Indian establishments. The pro- 
position has been entertained, and estimates are in course of preparation. No 
final decision has been yet however come to, though there seems no reason to 
_ fear that it will be unfavourable. The observations which have been received 
_ from these observatories have been partially examined by Dr. Lloyd, and 
_ awaiting the appearance of the observations themselves in a public form, 
_ the following remarks on them, so far as that examination has gone, will pro- 
_bably be considered interesting to the Association :— 
Extracts of a Letter from Dr. Lloyd to Sir J. Herschel. 
Bay is, “ Trinity College, Dublin, Feb. 12, 1845. 
__ “The observations made during the first year and a half at the East India 
‘ompany’s Observatories were transmitted to me from the Royal Society, and 
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