20 Mr. Glaisher on the Storm of October 30, 1863. [Nov. 26, 



during a heavy squall of \vind and rain, which passed over the ohservatory 

 at 3h. 30m. p.m. At this time, moreover, the readings of the several 

 other self-registering meteorological instruments at the Royal Observatory, 

 Greenwich, exhibited very large changes, and of so remarkable a character, 

 that the Astronomer Royal expressed a vAsh that I should bring them 

 under the notice of the Royal Society. The following are extracts from' 

 the several registers of the day mentioned : — 



At 6h. A.M., on October 30, the barometer read 29*32 in., and it com- 

 menced falling slowly after this time, reaching 29*30 in. at 8h. a.m. The 

 decrease then became more decided, and a steady fall was experienced ; 

 29*10 in. was reached by 0|h. p.m., and 28*96 in. by 2h. p.m. ; from 

 2h. P.M. to 2^h. P.M. the decline was very rapid ; and the minimum 

 reading, 28*80 in., was reached at the latter time. 



After 3h. 30m. p.m. the barometer turned to increase rapidly ; at 

 3h. 39m. P.M. it read 28*85 in. ; at 4h. p.m., 28*92 in. ; 4h. 20m. p.m., 

 29*00 in. ; at 5h. p.m., 29*07 in. ; and afterwards a gradual increase took 

 place to 29-30 in. by llh. p.m. 



At 8h. A.M., with the first indications of decided barometric fall, the 

 wind commenced to blow strongly from S.W. ; at 8h. 20m. a.m. it had 

 reached a force of I lb. on the square foot ; shortly after, 2 lbs., and at 

 8h. 30m. A.M. 3 lbs. A force of Ij lb. to 3 lbs generally prevailed, 

 till 9h. 25m. a.m. ; at 9h. 30m. a.m. a gust of short duration was ex- 

 perienced of 1 5 lbs., which produced a decline of temperature of 2°. From 

 9h. 35m. A.M. to 9h. 50m. a.m. the pressure of the wind varied between 



3 lbs. and 51bs. ; from 1 1 lb. to 3 lbs. from 9h. 59ra. a.m. to Oh. 45m. p.m. ; 

 there was no pressure for two or three minutes about Oh. 50m. p.m. ; the 

 wind then again commenced blowing strongly, reaching 4 lbs. at Oh. 55m. 

 p.m., and from 3 lbs. to 5 lbs. from Ih. p.m. to Ih. 15m. p.m., the 

 pressure was generally 2 lbs. to 4 lbs. from Ih. 15m. p.m. to 2h. p.m. ; 

 from 2h. Om. p.m. to 2h. 45m. p.m. it varied between 5 lb. and 2 lbs. ; the 

 wind again commenced blowing strongly, reached 3|lbs. at 2h. 50m. p.m., 



4 lbs. at 3h. p.m., 5 lbs. at 3h. 10m. p.m., 7 lbs. at 3h. 16m. p.m., 

 12 lbs. at 3h. 20m. p.m., 13 lbs. at 3h. 23m. p.m., 11 lbs. at 3h. 26m. 

 p.m., 17 lbs. at 3h. 29m. p.m., and 29|lbs. at 3h. 30m. p.m. ; then declined 

 suddenly, pressing with forces varying between 6 lbs. and 9 lbs. from 

 3h. 35m. P.M. to 3h. 45m, p.m., and 4 lbs. to 6 lbs. from 3h. 45m. 

 p.m. to 4h. P.M.; another gust at 4h. 10m. p.m. reached 8 lbs. ; again 

 declined to 4 lbs. at 4h. 15m. p.m.; after this time, till 5h. p.m., the 

 pressure varied between 2 lbs. and 4 lbs., between 2 lbs. and 3 lbs. from 

 5h. P.M. to 6h. P.M., from | lb. to 2 lbs. (with occasional lulls) from 

 6h. P.M. to 7h. P.M., from 2 lbs. to 4 lbs. from 7h. p.m. to 9h. p.m.; 

 scarcely any pressure was recorded between 9h. p.m. and lOh. p.m., and 

 from lOh. p.m. to llh. p.m. the amount varied between IJ lb. to 3 lbs. 



At the time of the great gust, viz. 3h. 30m. p.m., the barometer 

 reached its minimum, 28*80 in. ; the temperature declined rapidly (from 



