464 



DISCUSSIOX OF BAROMETRIC OBSERVATIONS. 



brevity, as it is in every case 29 inches. The computation was ex- 

 tended to four phices of decimals, though it has been thought unneces- 

 sary to give more than three. 



Table I. 



Atmospheric pressure for every day in the year— from the periodic function. 



Day of the month. 



9. 

 10 

 11. 

 12. 

 13. 

 14. 

 15. 

 16. 

 17. 

 18. 

 19. 

 20. 

 21. 

 22. 

 23. 

 24 

 25. 

 26. 

 27. 

 28. 

 29. 

 30. 

 31. 



Means 



Means from record. 



Means from corrected 

 record 



785 

 786 

 786 

 787 

 787 

 787 

 788 

 788 

 788 

 787 

 787 

 787 

 786 

 785 

 784 

 784 

 783 

 781 

 780 

 779 

 777 

 776 

 774 

 772 

 770 

 768 

 766 

 764 

 762 

 760 

 758 



7791 

 7740 



+ 57 

 7727 



756 

 753 

 751 

 749 

 746 

 744 

 742 

 739 

 737 

 735 

 782 

 730 

 728 

 726 

 724 

 721 

 719 

 717 

 715 

 713 

 711 

 710 

 708 

 706 

 705 

 703 

 701 

 700 

 699 



7255 

 7365 



-110 

 7351 



698 



697 

 096 

 695 

 693 

 692 

 691 

 690 

 689 

 689 

 688 

 687 

 686 

 686 

 685 

 684 

 684 

 683 

 682 

 682 

 681 

 68] 

 680 



679 

 679 

 678 

 678 

 677 

 677 



.6854 

 .6732 



+ 122 

 .6732 



677 

 676 

 676 

 675 

 675 

 674 

 674 

 673 

 673 

 672 

 672 

 671 

 671 

 670 

 670 

 669 

 669 

 668 

 668 

 667 

 667 

 666 

 606 

 666 

 665 

 665 

 664 

 604 

 664 

 063 



6696 

 0780 



-84 

 6818 



663 

 663 

 602 

 662 

 002 

 662 

 661 

 661 

 601 

 001 

 661 

 661 

 661 

 662 

 662 

 662 

 662 

 663 

 663 

 003 

 004 

 664 

 665 

 665 

 660 

 667 

 607 

 668 

 669 

 669 

 670 



671 



671 

 672 

 673 

 074 

 075 

 670 

 676 

 677 

 078 

 079 

 080 

 681 

 682 

 682 

 683 

 684 



693 

 693 

 694 

 694 

 695 

 695 

 695 

 690 

 696 

 697 

 697 

 697 

 698 

 698 

 099 

 099 

 700 



685 700 



685 

 686 

 687 

 687 

 088 

 089 

 090 

 690 

 691 

 691 

 692 

 692 



0030 .0822 



0588 . 6806 . 7057 



701 

 701 

 702 

 702 

 703 

 704 

 704 

 705 

 700 

 707 

 708 

 709 

 710 



785 

 783 

 782 

 781 

 779 

 777 

 776 

 774 

 772 

 770 

 708 

 706 

 703 

 701 

 759 

 750 

 751 

 752 

 749 

 747 

 744 

 742 

 740 

 737 

 735 

 733 

 730 

 728 

 720 

 724 

 722 



720 

 719 

 717 

 715 

 714 

 712 

 712 

 710 

 709 

 709 

 708 

 707 

 707 

 707 

 707 

 707 

 707 

 707 

 708 

 708 

 709 

 710 

 711 

 712 

 713 

 715 

 716 

 218 

 720 

 721 



+48 

 6594 



+16 

 6822 



-58 

 6978 



.7354 L7835 

 .7250 1.7968 



+104 

 .7280 



-133 

 7954 



7558 '.7118 

 7506 . 7068 



+47 

 7516 



+ 50 

 .7094 



725 

 725 

 727 

 729 

 73.J 

 7?4 

 V36 

 738 

 741 

 743 

 745 

 748 

 750 

 752 

 755 

 757 

 759 

 761 

 764 

 766 

 708 

 770 

 772 

 774 

 775 

 777 

 778 

 780 

 781 

 783 

 784 



.7557 

 .7624 



-67 

 .7624 



It here appears that the extremes of the annual fluctuation are the 

 maximum 29.7902 on the day of the autumnal equinox, with the mini- 

 mum 29.6612 on May 10, while a subordinate wave occurs in the begin- 

 ning of the decline from the September maximum, reaching a minimum 

 value of 29.7066 in the middle of November, with a subsequent rise to 

 29.7877 on the 8th of January. 



The most marked deviation between the monthly means of the com- 

 puted normal values and the means which were the basis of comi^uta- 

 tion, aside from those which are due to maxima or minima already ex- 

 posed, is found in the months of March and April ; and this is due to a 

 deviation from the regular progress occurring in the end of March, 

 whi^h will be noticed hereafter in its proper place. 



It is well known that the accidental barometric oscillations have a 

 greater range in the winter than in the summer months, and for the 

 purpose of obtaining a quantitative determination of the normal degree 



