360 



Results of Makeestoun Observations, 1844. 



29 days to 1 day, New Moon, 



2 5 ... 



6 9 ... 



10 13 ... 



0-003436 

 0-003058 

 0003874 

 0-004982 



Variations of the Diurnal Ranges of the Horizontal Component, with reference to the Moon's Age. — The 

 means in the first portion of Table XXV. shew that the diurnal range of the horizontal component is a minimum 

 about conjunction, and a maximum about opposition. The same result has already been obtained for the mag- 

 netic declination. The following are means of groups : — 



14 days to 16 davs, Full Moon, 0-004710 



17 20 ..'. 0-004235 



21 24 ... 0-003127 



25 28 ... 0-002936 



There is the appearance of a secondary maximum at new moon. The remarks ah-eady made in the 

 case of the magnetic declination. Table IV., are equally applicable here. In the case of this period, as well as 

 that for the year, it appears that the diurnal range is a maximum when the horizontal component is a minimum, 

 and vice versa. 



Variations of the Diurnal Range of the Horizontal Component with reference to the Moon's Declination. — 

 From the second portion of Table XXV., the diurnal range is a minunum when the moon has its greatest 

 south and also its greatest north declination, and it is a maximum when the moon is near to, hut north of, 

 the equator. This result is also the same as that obtained for the magnetic declination. The following 

 are means of groups : — 



27 day: 

 2 



6 

 9 



s to 



1 day. Moon farthest north, 0-003267 



5 davs, 0-004481 



8 .!. 0-004115 



12 ... 0-003401 



13 days to 15 days. Moon farthest south, 0-003248 

 16 ..'.... 19 ... 0-003546 



20 22 ... 0-003682 



23 26 ... 0-004311 



Here, also, as for the magnetic declination, we can say generally, that the diurnal range of the horizontal 

 component of magnetic force is less when the sun or moon has its greatest north or south declination, than at 

 the intermediate ])eriods. In this case, also, the diurnal range is a maximum when the horizontal component 

 is a minimum, and vice versa. 



TABLE XXVI. — Hourly Means of tlie Scale Readings of the Bifilar Magnetometer, corrected for 



Temperature, 1844. 



Div. 



517-59 

 517-59 

 51703 

 518-27 

 519-45 

 520-80 

 520-84 

 520-84 

 519-66 

 518-65 

 516-40 

 516-72 

 317-76 

 519-96 

 521-33 

 520-09 

 521-11 

 520-33 

 51915 

 517-77 

 519-45 

 518-70 

 518-48 

 518-53 



Feb. 



S.-. Div. 



520-39 

 518-69 

 517-96 

 518-64 

 518-75 

 522-22 

 521-26 

 521-30 

 521-41 

 519-40 

 518-02 

 517-12 

 519-05 

 521-56 

 523-37 

 ! 522-83 

 1522-16 

 521-10 

 521-38 

 521-03 

 522-08 

 521-35 

 518-64 

 518-08 



I 



518-79 

 513-74 

 514 61 

 516-98 

 518-29 

 516-59 

 521-33 

 519-37 

 515-05 

 511-93 

 510-39 

 512-27 

 514-50 

 520-62 

 521 54 

 524-66 

 525-78 

 526-07 

 523-32 

 52605 

 525-61 

 519-38 

 518-08 

 521-29 



April. 



521-08 

 522-56 

 520-81 

 518-00 

 520- 12 

 521-47 

 520-48 

 517-03 

 511-67 

 508-25 

 568-71 

 509-82 

 516-48 

 520-15 

 523-81 

 526-40 

 527-64 

 532-38 

 531-59 

 528-53 

 527-72 

 525-22 

 526-81 

 523-55 



May. 



Si-. Div. 



525-54 

 525-33 

 524-28 

 523-13 

 521-86 

 523-46 

 522-42 

 520-35 

 516-42 

 514-63 

 513-87 

 516-35 

 521-60 

 524-64 

 528-62 

 530-02 

 536-66 

 538-35 

 539-90 

 538-54 

 535-35 

 532-11 

 530-23 

 527-12 



Sc. Div. 



532-85 

 531-84 

 531-11 

 530-63 

 529-43 

 529-12 

 526-47 

 524-81 

 521-32 

 518-94 

 518-95 

 521-94 

 527-21 

 531-16 

 535-35 

 53700 

 539-09 

 540-80 

 541-33 

 541-65 

 539-77 

 537-73 

 536-47 

 533-66 



July. 



Sc. Div. 

 534-32 

 533-56 

 532-59 

 531-69 

 530-93 

 530-U 

 52916 

 526-24 

 523-01 

 519-07 

 518-18 

 521-54 

 527-27 

 532-41 

 536-26 

 538-78 

 540-32 

 541-62 



j 544-30 

 544-08 



1540-39 

 538-0 

 536-68 

 535-27 



Aug. 



Sc. Div. 



532-16 

 530-62 

 530-28 

 529-88 

 530-21 

 528-06 

 527-62 

 523-58 

 518-53 

 517-50 

 517-90 

 522-34 

 526-45 

 532-67 

 536-19 

 538-87 

 538-67 

 542-51 

 541-47 

 541-04 

 539-38 

 536-01 

 535-99 

 532-22 



Sept. 



-Sc. J>iv. 



532-56 

 532-84 

 530-93 

 53219 

 532-28 

 533-18 

 530-85 

 526-34 

 523-68 

 519-73 

 516-92 

 521-01 

 524-99 

 530-84 

 533-52 

 534-35 

 537-98 

 536-70 

 536-84 

 536-77 

 536-23 

 536-34 

 535-52 

 534-73 



Oct. 



Sr. Il 



532 

 531 

 531 

 533 

 532 

 531 

 531 

 530 

 525 

 521 

 519 

 523 

 527 

 531 

 532 

 535 

 535 

 536 

 534 

 533 

 534 

 533 



Nov. 



533-72 

 532-08 



1 



Sc. Div. 

 532-60 

 532-67 

 532-40 

 534-19 

 535-28 

 535-75 

 537-27 

 536-49 

 535-15 

 530-97 

 528-63 

 528-76 

 533-28 

 533-53 

 535-02 

 535-.30 

 534-13 

 537-95 

 537-06 

 534-13 

 534-91 

 532-69 

 532-85 

 531-66 



So. Div. 



535-72 

 5.36-74 

 535-40 

 535-96 

 538-06 

 53908 

 540-01 

 540-08 

 538-33 

 536-52 

 5.34-65 

 53492 

 536-22 

 536-86 

 537-86 

 538-23 

 53S-19 

 537-88 

 537-94 

 537-46 

 539-07 

 536-33 

 535-64 

 536-32 



Year. 



Sc. Div. 



527-99 

 527-31 

 526-57 

 526-91 

 527-28 

 527-65 

 527-42 

 525-59 

 522-48 

 519-75 

 518-51 

 520-50 

 524-37 

 527-96 

 530-47 

 531-84 

 533-11 

 5-34-31 

 534-05 

 533-40 

 532-83 

 530-58 

 529-93 

 528-71 



The true mean time at Makerstoun is lO"' in advance of the hours given in the second column of Table XXVI. 



