EF. Loomis— Observations of the U. S. Signal Service. 99 
We see that at Philadelphia the amount of rain which falls 
while the barometer is descending, is nearly three times as great 
as that which falls while the barometer is rising, and during 
the six colder months of the year the rain-fall in the former 
Relation of rain-fall to barometric pressure. 
Philadelphia! Valencia Armagh Falmouth Glasgow | Stonyhurst 
four years. | one year. one year. one year. one year. one year. 
z 
5 
Fall.) Ris’g, Fall, Fall.| Ris’g| Fall.) Ris’g| Fall.| Ris’g| Fall.| Ris’g 
Jan. | 2°36 | 0°42 | 2°90 | 2°04 | 1:46 | 0°49 | 3°52 | 2°92 | 2°13 | 1°18 | 3°38 | 1°54 
Feb. | 1°20 | 0°29 | 3°62 | 1-46/ 1°64] °31| 2°95} °85| °53] -28)1°11| °63 
March | 2°06 | 0:33 | 1°65 | 1°01/1°08| °49| °89| °76/ 2°24) °70/5°26| -95 
Apri 34| 0°97 | 2°64] 1°31 | -88| °70| 1°83} °83]1°02} -72)115| -49 
May 95/058] 60! -44|) -91! °18/1:°05| °21/1°99! -50| -65! 98 
June | 2°22|0 93] 53] -46| °37) 1°85 63 5/1] 
July | 2°03 | 2°63 | 3°31] 1°65 | -22| 70/115) 56/269) -99/1:97| 1°07 
Aug. | 3°98 | 1°39 | 4:03 | 1-27 | 2°05} 1°75 | 2°93 | -67 | 3-14 | 1°24 | 3°95 | 3-07 
Sept. | 1°67 | 0°50 | 4°14 | 2-23 | 1°96 | 1°20 | 4-04 | 1-96 | 2°50 | 1°50 | 3-38 | 2-09 
Oct. 1:43 | 0°52 | 5°28 | 1°96 | 2°60 | 1:04 | 5-01 | 1°60 | 5-67 | 1°62 | 3°69 | 2°95 
Nov. | 2°60 | 0-48 | 3°45 | 1°08 | 2°12] °76|3°84| -76 | 2°61 | 1°15 | 3°19 | 1-40 
Dee 3°19 | 0°68 | 5°17 | 2°06 | 1°91] °91 | 6°44} 2°66] 1°66} 41) 2°81) °85 
Year |27-03! 9°37 |37-72117-04|17-29' 8-90 |35°50!14°65|26°71!10°44/31-70116°37 
i : 2°42 2°56 1:94 
Aberdeen Kew Paris Brussels Prague Vienna 
one year. one year. one year. (six months.|three years, ‘three years, 
Fall.| Ris’g| Fall.| Ris’g| Fall.| Ris’g) Fall.| Ris’g) Fall.) Ris’g) Fall.) Ris'’g 
Jan. | 1:04 | 0°27 | 0°53 | 0°43 | 1°55 | 0°56 0°30 0°27 [0°88 |0°42 
Feb. |1:25| 43] -82| -29] °55| °37|1°6911°56| °78| 46| °57)} °68 
March] °65/1°97| -22| -21| *61| °15| -30] -50| 80] ‘86! 12] -22 
April | °55| °53/1°04| -22| -83| 1-45 1:52] -90] °31| 55] 08} -32 
May *64| -331 -27 0| 0O| -76| 53] 47! -76|1°13 11°02 
June | 1:00) -12!1:55| -99| 2°58 | 1-94 }1-02 {2°79 |1°00 |1°34 |1°04 |1-09 
July /|1:18|}1°16| -88| °39| 1°68 | 1°07 |1°93 |2°82| 63 |1°41| -42 |2°26 
Aug. | 3°99 | 2-69 | 1:04 60 {1°16 |1°10 |1°45 
Sept. [1-23] -96/2-07| -73|161| °47 -10| 52} -47 |1-02 
23| 1-06} 2°00] 1°72} “T1| -87 10} -48| -49| -42 
Nov. | 2°35/1-°36/1:°52| -62| -28| 09 46| 53/130] 52 
03/1712! -42 9| 15 57 | 41] 73] 35 
Year |16°12!13-22|13°12) 6°53 |11°53! 7°76 | 7°12! 9°10/6°42 | 8°75) 8-33! 9-67 
Ratio 1°22 2°01 1-49 0-78 0-73 0°86 
case is nearly five times as great as in the latter case. In sum- 
mer there frequently occurs a thunder shower with an excessive 
of rain accompanied by a slight rise of the barometer, and 
this affords the explanation of the fact that in July more rain 
nd, the amount of rain with a falling barometer is more than 
twice that with a rising barometer; but this ratio rapidly dimin- 
