Magnetic Dip. 



391 



Variations of Magnetic Dip with reference to the Moon's Age. — An examination of the mean variations in 

 the first portion of Table LIV. wall shew that the magnetic dip is a maximum when the moon is in opposition, 

 and a minimum when in conjunction. This result is also evident in the following means of groups : — 



14 days to 16 days, Full Moon, 



17 20 ... 



21 24 ••• 



25 28 ... 



0'-456 



29 days to 1 day, New Moon, 



0'-064 



0'-540 





0'-062 



0'-328 



6 9 ... 



0'-215 



0'-085 



10 13 ... 



0'-511 



This result agrees generally with that obtained from the incomplete series of observations for 1843. In 

 1843 there was the appearance of a secondary maximum at conjunction ; in 1844 there is the appearance of a 

 secondary minimum at opposition. 



Variations of Magnetic Dip with reference to the Moon's Position in Declination. — The general appear- 

 ance of the quantities in the second portion of Table LIV. is that of a maximum of magnetic dip when the 

 moon is near the equator, and a minimum when it is farthest north and farthest south. The following are 

 means of groups : — 



27 days to 1 day, 



2 5 days, 



6 8 ... 



9 12 ... 



Moon farthest North, 0'-176 

 0'-245 

 0'-390 

 0'-222 



13 days to 15 days, Moon farthest South, O'TIO 



16 19 ... 0'-156 



20 22 ... 0'-342 



23 26 ... 0'-404 



Both maxima occur when the moon is from one to three days north of the equator, 

 partially obtained from the incomplete series of observations for 1843. 



This result was onlv 



TABLE LV. — Diurnal Variations of Magnetic Dip for each Month in 1844, as deduced from 



Tables XXVII. and XLIIL 



"■ ■ 



Mak. 

 M. T. 



Jan. 



Feb. 



March. 



April. 



May. 



June. 



July. 



Aug. 



Sept. 



Oct. 



Nov. 



Dec. 



Year. 



h. 



12 



0-578 



0-311 



0-592 



0-943 



1-561 



1-137 



1-230 



0-924 



0-257 



0-294 



0-589 



f 

 0-662 



0-489 



13 



0-606 



0-547 



1-278 



0-811 



1-608 



1-234 



1-310 



1-172 



0-245 



0-355 



0-589 



0-540 



0-591 



14 



0-663 



0-655 



1-111 



1-096 



1-748 



1-346 



1-457 



1-193 



0-536 



0-340 



0-679 



0-683 



0-692 



15 



0-439 



0-535 



0-836 



1-486 



1-959 



1-471 



1-633 



1-354 



0-336 



0-011 



0-421 



0-597 



0-656 



16 



0-219 



0-535 



0-692 



1-155 



2-178 



1-667 



1-793 



1-395 



0-365 



0-000 



0-266 



0-280 



0-611 



17 



0-000 



0-016 



0-923 



0-969 



2015 



1-742 



1-943 



1-775 



0-281 



0-213 



0-207 



0126 



0-583 



18 



0-012 



0-169 



0-283 



1-223 



2-238 



2-149 



2074 



1-836 



0-674 



0-407 



0-000 



0-000 



0-655 



19 



0-032 



0-173 



0-708 



1-829 



2-579 



2-406 



2-494 



2-474 



1-402 



0-623 



0133 



0017 



0-972 



20 



0-250 



0155 



1-431 



2-670 



3-181 



2-917 



2-934 



3-227 



1-840 



1-453 



0-345 



0-296 



1-458 



21 



0-427 



0-455 



1-905 



3-190 



3-435 



3-209 



3-486 



3-344 



2-452 



2-124 



0-978 



0-561 



1-863 



22 



0-781 



0-660 



2120 



3-100 



3-494 



3-147 



3-603 



3-251 



2-856 



2-438 



1-337 



0-838 



2-035 



23 



0-766 



0-824 



1-880 



2-962 



3-124 



2-643 



3-056 



2-564 



2-222 



1-891 



1-365 



0-8)8 



1-742 







0-635 



0-568 



1-549 



2053 



2-366 



1-880 



2-213 



1-960 



1-641 



1-332 



0-799 



0-646 



1-203 



1 



0-349 



0-227 



0-719 



1-493 



1-955 



1-322 



1-496 



1-118 



0-851 



0-836 



0-785 



0-579 



0-710 



2 



0-184 



0-000 



0-704 



1-037 



1-418 



0-751 



0-971 



0-688 



0-539 



0-648 



0-604 



0-477 



0-401 



3 



0-371 



0-131 



0-292 



0-745 



1-287 



0-572 



0-710 



0-406 



0-538 



0-319 



0-694 



0-477 



0-278 



4 



0-206 



0-279 



0-149 



0-581 



0-397 



0-349 



0-584 



0-507 



0-092 



0-301 



0-978 



0-490 



0-142 



5 



0-341 



0-429 



0-159 



0-000 



0-230 



0-121 



0-434 



0-000 



0-296 



0-240 



0-418 



0-540 



0-000 



6 



0-515 



0-400 



0-549 



0-146 



0000 



0-062 



0-000 



0-174 



0-202 



0-401 



0-498 



0-595 



0-028 



7 



0-723 



0-421 



0-052 



0-510 



0-186 



0-000 



0-047 



01 72 



0-119 



0-498 



0-805 



0-617 



0-078 



8 



0-459 



0-242 



0-000 



0-485 



0-632 



0-264 



0-548 



0-354 



0116 



0-329 



0-565 



0-344 



0-094 



9 



0-546 



0-252 



0-729 



0-733 



1-023 



0-519 



0-811 



0-712 



0-000 



0-336 



0-801 



0-707 



0-330 



10 



0-480 



0-641 



0-665 



0-395 



1173 



0-630 



0-959 



0-584 



0048 



0-166 



0-654 



0-777 



0-330 



11 



0-457 



0-597 



0-279 



0-765 



1-520 



1017 



1-103 



0-975 



0-075 



0-385 



0-774 



0-622 



0-447 



