Waves of sand and snow and the eddies which make them . ts bluntend to windward and for the travelling drifts orwaves to leeward, at least as far as their verticalprofile was concerned (Fig. 15). The stationary drifts, when complete, filled thewhole curve. The travelling drifts or wavesoccupied only part of it. I was at first satisfiedby the mere fact that I had recognized utiity of formamong the fantastic shapes assumed by snowdrifts Fig. 15 The Pundamental curve ofsnow dri-Fts. at various stages of their growth in the neighbour-hood of obstructions of diverse kinds, but Ipresently realized t
Waves of sand and snow and the eddies which make them . ts bluntend to windward and for the travelling drifts orwaves to leeward, at least as far as their verticalprofile was concerned (Fig. 15). The stationary drifts, when complete, filled thewhole curve. The travelling drifts or wavesoccupied only part of it. I was at first satisfiedby the mere fact that I had recognized utiity of formamong the fantastic shapes assumed by snowdrifts Fig. 15 The Pundamental curve ofsnow dri-Fts. at various stages of their growth in the neighbour-hood of obstructions of diverse kinds, but Ipresently realized that the general curve which Ihad drawn so as to satisfy my eye had a widesignificance, that it was one familiar in otheraspects of nature than snowdrifts—that it was, infact, the containing curve of eddies. The recog-nition of this fact made it much easier to under-stand the mode of formation and the movementsof the structures I had been examining in bothsand and snow, particularly when extending theirstudy to three dimensions and not dealing merely. 155 SNOW-WAVES AND SNOW-RIPPLES 157 with the profile, which is all that is generally studiedin waves. The general form of an eddy can be observedby fixing a board in a vertical position athwart astream, the board being just submerged. The con-taining curve of the eddy is then easily traced bythe disturbance on the surface of the is seen to be eddying disturbance for ashort distance up-stream; its margin passes closeto the edge of the board in a direction slightlyinclined outwards, the greatest width of the eddy-curve being a little to leeward of the this position the border of the eddy closesin very gradually, so that the tail of the disturbanceis situated far to leeward of the obstruction. Thedistance from the shoulder, or position ofgreatest width, to the tail is several timesgreater than that from the commencement ofeddying on the weather side to the shoulder. Theoutline as one looks down upon the
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Keywords: ., bookcentury1900, bookdecade1910, bookidwavesofs, booksubjectwaves
