Lovering and Bond on Magnetic Observations at Cambridge. 25 
affecting its magnetic equilibrium; all of which come, with few ex- 
ceptions, under the same general expressions so much so as to 
leave no doubt that they have a common origin. Hence it might 
be expected that if the corresponding curves of magnetic Declina- 
tion were drawn for the same solar time in different places they 
would conform to each other and exhibit a kind of parallelism. 
But in addition to the orderly variations there are other perturba- 
tions of a sudden and irregular nature; and it becomes an object of 
extreme interest to inquire how far these are local and accidental 
and to what extent they must be regarded as general and proceed- 
ing from some grand central force. Such an examination was con- 
templated as among the good results of the simultaneous observa- 
tions made in Germany, Russia, Italy, &c., an account of which 
may be found in Taylor’s “ Scientific Memoirs ” and “'The Russian 
- Magnetic Annual” to which I have already referred ; and a possible 
answer to an intricate question was held out as an inducement to 
engage in the magnetic crusade. The expected comparison ex- 
hibits surprising coincidences in most of the irregular movements of 
the Magnetometer as if the cause were coextensive with the range of 
magnetic posts. Hitherto our country and indeed this whole West- 
ern Continent has not been represented in this Congress of Nations 
for a scientific object ; having been destitute of the means of contrib- 
uting its portion to the general levy which has been made upon them. 
But the Term-day observations at Toronto, U. C., Philadelphia, 
and Cambridge will furnish materials for doing this now. Plate III. 
exhibits the diurnal curves of the October Term-day for the mag- 
netic Observatories of Toronto and Cambridge. The declination 
of the meridian was very considerably deranged by perturbations 
during the first 12 hours of the Magnetic day (which always begins 
at 10 P.M. of Gott. M. T.) and affords, therefore, a favorable opportu- 
4 
