SIGNS ON THE BEACH 3 



causes, in the aggregate, considerable vibrations. Such sands 

 are not uncommon, having been recorded in many places, and 

 they exist probably in many others where they have escaped 

 observation. They may be looked for above the water-line, 

 where the sand is dry and clean. 



We have to do, however, in this volume, not with the history 

 of the past, nor with the action of physical forces, but with the 

 life of the present, and to find this, in its abundance, one must 

 go down near the margin of the water, where the sands are wet. 

 There is no solitude here ; the place is teeming with living things. 

 As each wave retreats, little bubbles of air are plentiful in its 

 wake. Underneath the sand, where each bubble rose, lives some 

 creature, usually a mollusk, perhaps the razor-shell Solen ensis. 

 By the jet of water which spurts out of the sand, the common 

 clam Mya arenaria reveals the secret of its abiding-place. A 

 curious groove or furrow here and there leads to a spot where 

 Polynices heros has gone below; and the many shells scattered 

 about, pierced with circular holes, tell how Polynices and Nassa 

 made their breakfast and their dinner. Only the lifting of a 

 shovelful of sand at the water's edge is needed to disclose the 

 populous community of mollusks, worms, and crustaceans living 

 at our feet, just out of sight. 



Even the tracks and traces of these little beings are full of 

 information. What may be read in the track of a bird on the 

 sand is thus described by a noted ornithologist : 



Here are foot-notes again, this time of real steps from real 

 feet. . . . The imprints are in two parallel lines, an inch or 

 so apart ; each impression is two or three inches in advance 

 of the next one behind ; none of them are in pairs, but each 

 one of one line is opposite the middle of the interval between 

 two of the other line ; they are steps as regular as a man's, 

 only so small. Each mark is fan-shaped ; it consists of three 

 little lines less than an inch long, spreading apart at one ex- 

 tremity, joined at the other. At the joined end, and also just 

 in front of it, a flat depression of the sand is barely visible. 

 Now following the track, we see it run straight a yard or 



