6 E. Loomis— Observations of the U. 8. Signal Service. 
diminishing intensity. On the morning of the 20th, the great- 
est depression was at Bismark, 29-48; on the morning of the 
21st, at Keokuk, 29°75; on the 22d, at Alpena, 29°74; on the 
23d, at Sydney, 29°54, and during the next two days the depres- 
sion still further increased. Another low area had now arrived 
at Nova Scotia, and on the 26th had approached so near the 
former that the two seemed inclined to coalesce. On the two 
following days this tendency became more decided, and on the 
29th both were united in one great depression, the pressure 
near the center being 28°94. This low area advanced towa 
the northeast without any perceptible diminution of intensity ; 
but when it had nearly reached the North Cape, its course was — 
turned to the southeast. The center of this low area has thus — 
in or near the Gulf of Mexico. The following cases are not 
on the maps of the United States Signal Service: 
1, 1874, Sept. 5- 7. 4, 1875, Sept. 14-19. 
2, “. Sept. 9-11. rs | Oe ee 
3. >) Sent, 27-80. 8. 8 Now 1k 
