418 



Report of Magnetical Observations at 



0-18000 + (C.G-.S. units). 



Table III. — Hourly Means of the Horizontal Force at Falmouth 



on Five selected quiet Days in 



Hours 



Mid. 



1 



2 



3 



4 



5 



• 1 



7 



8 



9 



10 



11 



Winter. 



1900. 



























Jan. . . 



671 



670 



671 



671 



673 



674 



676 



677 



675 



669 



663 



660 



Feb. .. 



672 



672 



672 



673 



673 



674 



675 



674 



673 



669 



663 



662 



March . 



679 



680 



679 



679 



679 



679 



678 



678 



675 



666 



662 



657 



'Oct. .. 



696 



696 



694 



695 



697 



698 



699 



698 



695 



685 



676 



672 



Nov. .. 



706 



706 



706 



706 



707 



708 



708 



707 



703 



696 



692 



694 



Dec. .. 



701 



701 



702 

 • 



703 



703 



704 



704 



704 



704 



703 



701 



699 



Means 



688 



688 



687 



688 



689 



690 



690 



690 



6S8 



681 



676 



674 



Summer. 





April , . 



687 



686 



686 



687 



686 



686 



685 



686 



683 



678 



668 



665 



May .. 



687 



685 



683 



683 



682 



680 



676 



672 



668 



666 



666 



667 



June . . 



700 



699 



697 



697 



698 



698 



695 



692 



687 



681 



675 



673 



July .. 



702 



701 



699 



698 



698 



697 



695 



693 



687 



679 



671 



672 



Aug. .. 



701 



700 



698 



698 



697 



697 



693 



688 



681 



673 



674 



680 



Sept. . . 



707 



705 



704 



703 



704 



702 



701 



697 



691 



685 



681 



681 



Means 



697 







696 



695 



694 



694 



693 



691 



688 



683 



677 



673 



673 



* Mean of four days— 2nd, 7th, 13th, 31st. 



Table IV. — Diurnal Inequality of the Falmouth 



Hoursj Mid - 12 



[ 



3 



4 5 



6 



I 



7 8 



9 



10 



11 



Summer mean. 



+ '00005 + -00004;+ '00003 + -00002 



1 1 ! 



+ -00002 + -00001 



- -00001 



- -00004 



- -00009 



- -00015 



- -00019 - -00019 



Winter mean. 



1 i 1 

 + -00002 + -00002 + -00001 



+ -00002 + -00003 + -00004 



+ -00004 



+ -00004 



+ -C0002 



- -00005 



- -00010 



- -00012 



Annual mean. 



| + -00004 + -00003'+ -00002 



III' 



+ -0C002 



+ -00003 + -00003 + -00002 1 



i 1 1 



•00000 



- -00004— -00010 



- -00015 



- -00016 



Note. — When the sign is + the reading 



