122 - REPORT—1845. 
the aqueous vapour. The normal wave of the gaseous atmosphere is there- 
fore greatly modified by the pressure of the aqueous vapour in these projec- 
tions, 
TABLE X. 
Ordinates of the Mean Normal Curve, deduced from the recurring Curves | 
of 1842, 1843, 1844, November. 
| 
(ones Pe | altitudes, ||, Hours af | attitudes. | Hours be: | attitudes. | pours af | altitudes. 
hours. in. i hours. in. | hours. in, hours. in. 
Apex 30°321 ||Apex 30°32] || 76 — | 29°775 + | 29-789 
pee 330 | 2 + 302 || 78 — ‘766 || 78 + 788 : 
by ioe ‘331 | res ‘301 | 80 — 758 || 80 + 771 ! 
oe $27 || 6 + 298 || 82 — 758 || 82 + “755 
ee 323 || 8 + 295 || 84 — ‘761 || 84 + 733 
cee 321 || 10 + 302 | 86 — 763 || 86 + 717 
1g jen 314 || 12 + 300 || 88 — ‘760 || 88 + 696 
PAs cs 299 || 14 + 296 || 90 — 748 || 90 + 667 
Ae 274 || 16 + 278 || 92 — 747 || 92 4+ -630 
1s. 2 229 || 18 + 26] || 94 — 735 || 94 + 590 
20 — 204 || 20° + 236 || 96 — -730 || 96 + “555 
22 = 169 || 22) + 204 || 98 — 722 || 98 + 548 
24 — “152 | 24 + 169 ||100  — 712 100 + 546 
2% — “132 || 26 +4 -130 [102 — 689 ||102 + “555 
28 — 106 || 28 + 091 |104. — “682/104 + -562 
a0. s 081 || 30 + 061 1106 — ‘687 106 + 558 
32 — 057 || 32 + | 30031 }108 — -687 |108 + 565 
pg -026 || 34. + | 29986 |110 — 681 |110 + 571 
36 — | 30-006 || 36 + 968 |112 — 675 |112 + 576 
38 — | 29-991 || 38 + 941 114. — 664 114 + 583 
40 967 || 40 + 933 |116 — 669 |116 + 590 
a= ‘941 || 42 4 934 |118  — 685 |118 + 589 
44 — ‘919 || 44 4 943 | 120 ~— -728 |120 + 578 
a 909 || 46 + ‘956 |122  — 744 |\122 0 +4 552 
ag 908 | 48 + 950 |124 — 74) 1124 538 
50 — 900 || 50 + 932 |126 — 734 126 -498 
cee “892 || 52 + 932 |128  — 722 |\128 + +459 
4 i 883 || 54. + 924 |130 — 711 130 + 405 
56 — 866 || 56 + ‘914 |132  — “688 132 + "332 
58 — 853 || 58 4 895/134 — “659 {1134 + 
60 — 843 || 66 + 883/136 — 625 136 + 
62 — 835 || 20 + 871 138 — 588 [138 + 
Gd ws “821 | 64 + 870 |140  — 532 140 + 179 
66 — 811 || 66 + 862 [142 — 482/142 + 214 
68 — 809 || 68 + 845 [144 — “455 144 4 +240 
70 — “791 | 70 + 841/146 — 428 |146 + 255 
: ee 794 | 72 + 829/148 — | 29-411 /148 +4 | 29-282 
74 — | 29-791 || 74 + | 29-803 || | 
4th. The curves are projected for one station only. It is not only proba- 
ble, but in the case of the curve for 1842 it has been ascertained, that even 
for comparative short distances N.E. and S.W. of the line joining Dublin 
and Munich, the symmetry is considerably departed from, as will be shown 
in the further examination of that curve; it is therefore important, as well as 
deducing the mean normal curve from a combination of the three curves at 
one ‘station, to examine the character of the superposed waves at several 
stations previous to drawing any conclusions relative to the normal wave. 
5th. The projections are affected by the diurnal and annual variations of — 
gaseous and aqueous pressure, the causes of which are known. a 
We have however the means of obtaining at four important stations, the © 
& 
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