18 CONTENTS 



The Eddy-form of Snow-Waves and Snowdrifts. 



Complex forms of drifts produced by fixed obstacles — 

 All contained by a boundary curve having blunt head 

 and fine tail — This is the boundary of the eddy caused 

 by the obstruction — Complex forms are stages of 

 filling in of eddy-space, and due to insufficient supply 

 of snow — The eddy-curve and its relation to the forms 

 of fish and cetaceans — of the wings of birds — of the 

 submerged part of ships — of torpedoes and non-rigid 

 airships — Forms of holes scoured out in snow round 

 the trunks of trees — Relation of snow-barchans to 

 the eddy-curve — The relation of form and movement 

 between the travelling crescentic snowdrifts and the 

 swirl made in water by an oar — Shape of the eddy in 

 snow-waves — Inference as to the distance to which 

 hedges and belts of trees extend shelter from wind. 



On the Three Modes of Deposition of Drifted Material 

 depending upon Rate of Subsidence. 



Behaviour of gravel, sand, and dust before the wind — 

 Of shingle, sand, and mud under the action of waves 

 and currents — Single tail of sand behind a narrow 

 obstacle — Double tail of snow-powder — Single train 

 of black smoke, but double track of steam, from 

 chimneys — How fallen leaves drift before the wind — 

 On " banner clouds " and on sandbanks to leeward of 

 promontories — On the action of an obliquely crossing 

 wind upon the swell of the sea. 



