E. Loomis— Observations of the U. S. Signal Service. 7 
vations in curve lines and find a general correspondence between 
the fluctuations of the barometer at the two stations, with some 
decided differences, among which the most noticeable is that 
the maxima and minima of pressure generally occur earlier at 
the base of the mountain than they do at the summit. The 
Barometer at base and summit of Mt. Washington. 
Date. Base. | Summit. Diff. 
Min. |May 3/12 m | 26-820] 2 p.m.| 23-390) +2). 
Max. 8! Ta.m.| 27°547|11 a.m.| 24°114; +4 
Min. 13) 2 P.m.} 26°654) 6 3:147| +4 
Max. 21} 8 a.m.| 27480] 9 a.m./ 24°055) +1 
Min. 24! 1 p.m.| 26-822) 5 p.M.| 23°422) +4 
Max. 26] 8am.| 27-346] 9 a.m.| 24°029 +1 
Min. 28! 4 p.m.| 26°988| 9 P.M.| 23°631) +5 
Max. 29110 a.m.| 27°187| 5 P.M.| 23°839, +7 
Min, 30/12 pw.) 27°114| 5 a.m.! 23°607; +5 
Max. 31! 9 a.m! 27-500) 4 P.m.| 24°021) +7 
Min. |June 5| 2 a.m} 26-756) 5 A.M.| 23°406) +3 
ie 8| 6 p.m.| 27°388) 6 P.M.| 24-040 et 
9} 5 A.m.| 27°393/11 a.M.| 24°012; +6 
Min. 11! 6 a.M.| 27°007| 9 a.m.) 23°670) +3 
Max. 13) 4 a.m.| 27°430/10 a.m.| 24°043) +6 
Min. 17| 2 a.m.| 26°952| 4 a.m.) 23°540) +2 
Max, 18} Sa.m.| 27-138|12 mM. | 23-748) +4 
Min. 20! 2 a.w.| 26-788} 4 a.m.| 23°468) +2 
Max. 25 10 Am.| 27°582/12M. | 24°270) +2 
Min. 28 4a.m.| 26°983| 5 P.m.| 23-708) +13 
; Several of these maxima and minima are represented on Plate 
» The upper curve represents the barometric fluctuations on 
