CONTENTS. 



On the Study of Double Stars by Amateur 



Observers. III. By G. F. Chambers. F.R.A.S. 381 

 The Chemistry of Inks in Handwriting. 



By C. Ainsu-ortli Mitchell. B.A. iOxoii). F.I.C. 387 

 Solar Disturbances During August, 1910. 



By Frank C. Dennett 390 

 The Destruction of Weeds by Chemical Means. 



By Harold C. Long. B.Sc. 391 

 The Habits of Caterpillars. 



By L.J. Winter Jnyiwr. 395 

 Sir William Christie and Greenwich 



Observatory. By F. S. Grew. .W..4. 397 



Stalactites. By George H. Martin. M.A.. F.C.S. 403 



Queries and Answers 405 



The Face of the Sky for October. 



By W. Shacklcton. F.R.A.S.. A.R.C.S. 406 

 The October JIeteoric Shower. 



By W. F. Denning. F.R.A.S. 407 



Correspondence... ... 



Notes. — 



Astronomy 



Botany. By Professor F. Cavers. D.Sc.. F.L.S 



Chemistry. 



By C. .Ainswortli Mitchell, B.A. >Oxon 

 Economic BioloKv. 



By Walter E. Collinge. M.Sc..F.r..S..F.E.S 

 Geology. By G. W. Tyrrell. A.R.C.S.. F.G.S 



Meteorolog\\ 



Microscopy. 



Photographv. 

 By 



Physics.' 



Zoolog\'. 

 Reviews 

 Notices 



By John A 

 By A. W 



Curtis. F.R.Met.Soc. 

 Sheppard. F.R.M.S. 



C. F. Kenneth Mees. D.Sc, F.C.S. 

 By W. D. Eggar. M.A. 



PACK. 



408 



409 

 409 



F.LC. 411 



412 

 413 

 413 

 414 



417 

 419 

 419 

 419 

 420 



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