METEOROLOGY. 415 



No. of paragraph. 

 Abbe, Prof. C. — Coutimied. 



Suildcii prcssnn^ cbaii-^c ;it Washiiifijton 270 



Diurnal variation of baroinotcr 276 



Hypsomotric foniiula of Laplace , 282 



Cbarts of storm frc(iueiK\, 283 



Causes of storm progress 287 



Oriftiu of ligbtniuor 295 



Locution of tb nnder-storms 295 



Obst-rvat ions of beat ligbtuing 296 



Distiibntion of tbnuder-stornis 296 



Gusf s preceding tbnnder-st orins 298 



Ou t be Kiippen-Espy tbeory of squalls aud gusts ;J00 



Structure of tbuuder- storms 305 



Systems of weatber cbauges 321 



Principal centers of action 323 



Long i-auge predictions 328 



Auroral arcbes in Uuited States 362 



Ind iau summer smoke baze 386 



Extraordinary twiligbt pbeuomeua of 1883-'84 387 



T\^ iligbt due to aqueous spberules 390 



Renewal in 1884 of twiligbts of 1883 399 



Nebulous cloud about tbe sun 401 



Sun-spot period in temperatures 414 



Vegetation during geological climate 425 



Tbcrmal constants for locust.s' eggs 429 



Abercromby, R. : 



Popular weatber sayings 97 



European weatber types 98 



Describes pocky clouds 207 



Abney, Captain, pbotograpby of aqueous absorption bands 373, 374 



Abney and Festing, spectra at low and bigb temperatures 374 



Actinometer: 



Hiin's .absolute 173 



Stewart's improved 174 



Stokes' improved 174 



Langley "s bolometer 179 



Frolicli's tbermopilo 180 



Aclinometry 173, ls3 



Ackroyd, W. , formation of rainbows 378 



Adamson, pbaMiological laws 421 



African coast, climate of 84 



Aerodynamics, experimental : 



Reynolds 213 264 



Darwin 214 



Vettin 263 



Airy, Sir G. B., temperature of tbe Tbames 196 



Aitken, dust pbeuomeua 208 



Agricultural experiraeuts, Hougbton farm 45 



Alcock, N., climate and complexion 432 



Algeria, climate of 83 



Allahabad, meteorology of 10 



Amstein, IL, barometer, self- registering 141 



Andries, Dr. P. : 



Origin of atmospberic electricity ; 310 



Formation of thunder-storms 310 



