34 
MR. A. W. RtiCRER AND DR. T. E. THORPE ON A MAGNETIC 
Tlie results were :— 
Mean of the four months, May to August . .... 17° 36'‘8 
,, ,, two ,, June and July.17° 36''5 
The secular change at Kew, according to our 1890 Memoir is — 6''3.o per annum. 
Hence the calculated Declination on July 1, 1892, deduced from this figure and the 
value for January 1, lb91, is 
17° 46'-2 ~ 6''35 X DS = 17° 3(/-7 
which falls between the results calculated from! the means of two and four months 
respectively. 
It is evident, therefore, that our published Table of secular change is in very close 
accord with fact, and as the differences between it and the new Table obtained in 
this paper from a comparison of the two surveys are insignificant when the period 
considered is only 18 months, we thought it best, as a general rule, to reduce the 
1892 observations to epoch by the same Table as tliat employed for 1890 and 1891. 
Results of the Observations. 
Although in tabulating the results of the observations we follow the same plan as 
that adopted in our previous paper, it is desirable to repeat in this place the facts 
which are necessary to explain it. 
The stations are arranged in the following order ;— 
Three groups are formed as before, comprising Scotland, England and Wales, and 
Ireland, respectively. 
In each group the whole number of stations at which observations were made in 
the two surveys, are arranged in alphabetical order, and are numbered continuously 
throughout. 
As the names are now printed on. the maps, it is unnecessary to enter these 
numbers on an index map as was previously done. 
In the subjoined abstracts of the results, those obtained in the previous survey are 
not repeated, but the names of the starions appear in their proper palaces, together 
with a reference to their positions, in our former memoir. (3f course, in the case of 
the “ repeat ” stations, the new data are fully given. 
The Scotch stations, from Aberdeen to Wigtown, are numbered from 1 to 244, and 
it should be mentioned tha.t the name of a Loch is reg-arded as determinino- the initial 
letter. Thus East Loch Tarbert is found under T. 
The English and Welsh stations, including the Isle of Man and the Channel Isles 
from Abergavenny to Yarmouth, are numbered from 245 to G96. 
The Irish stations from Annalong to Youghal, are nundiered from 697 to 882, 
