2 Lovering and Bond on Magnetic Observations at Cambridge. 
detailed in their Reports.* Regular magnetic observations were 
undertaken at Cambridge in March, 1840, being confined at first to 
the monthly Term-days of the English scheme. The meteorological 
observations recommended in the same Reports were also begun in 
a modified form, adapted to the resources of the Observatory, at that 
time; but it is not proposed to speak of them except so far as they 
may be connected with the remarks on Terrestrial Magnetism. The 
necessity of conforming, as near as possible, to the general plan and 
acting in concert is apparent, as the observations are intended rather 
for comparison than for independent use. But in the execution of 
this charge, as far as it has yet progressed, questions of curiosity or 
of higher interest have been constantly occurring which suggested 
the expediency of observations additional to, but not interfering with, 
the chief work. In some cases, these inquiries could be answered 
or the approximate data for a solution be derived from the means at 
our command; but often, they depended upon comparisons between 
elements simultaneously observed at different places. In the latter 
instances, we have had valuable assistance in the prompt codperation 
of Lieutenant C. J. B. Riddell at the Magnetic Observatory in To- 
ronto, U. C. The results of these extraordinary observations will 
be exhibited in their proper place. That an opportunity may be af- 
forded of judging of the degree of accuracy of the observations we 
shall first give a description of the plan of the Observatory, the 
nature, position and adjustment of the instruments, and the method 
of making the observations. 
Plate I. is a ground plan of the University Observatory. The 
* Royal Society. Report of the Committee of Physics, including Meteor- 
ology, on the Objects of Scientific inquiry in those sciences. London, 1840. 
Report upon a letter addressed by M. Le Baron de Humboldt to his Royal 
Highness the President of the Royal Society, and communicated by his Royal 
Highness to the Council 9th June, 1836. 
