Page:Popular Science Monthly Volume 70.djvu/561

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A BLAZING BEACH
557

A BLAZING BEACH

By D. P. PENHALLOW, D.Sc, F.R.S.C.

MACDONALD PROFESSOR OF BOTANY, MCGILL UNIVERSITY

IN December, 1905, an account was given in Science[1] of a remarkable phenomenon which was described as 'A Blazing Beach' as observed at Kittery Point, Maine, and an attempt was then made to bring forward an explanation which would satisfactorily account for all the observed facts. During the past summer an opportunity was offered for a reexamination of the locality, and it was then possible to obtain some additional facts which tend to strengthen the conclusions originally reached. It was also learned that a second but smaller conflagration had occurred in the same place at a somewhat later date. It is therefore felt that a further account of the facts will be of interest at this time.

The accompanying photograph, taken during the past summer, shows the precise area within which the conflagration developed. The beach at the point where the fire occurred is composed of a barrier ridge at its upper margin, made up of pebbles of varying sizes. This ridge is thrown up and maintained under the action of southeast storms, at the angle of repose for the material of which it is composed, and about half-way down its outer face, the high water mark of spring tides is clearly indicated by patches of sea-weed. This high-water mark corresponds approximately to the level of the interior area where the trees are to be seen growing, and which is frequently flooded in times of severe southeasterly storms. The base of the barrier ridge is indicated by the line of sea-weed which defines the high-water mark of the ordinary neap tides. From this point the beach, consisting of pebbles, continues outward and downward at a somewhat sharp incline for a distance of about seventy-five feet, when the pebbles are replaced by sand, the first patch of which is seen just above the line of water. The photograph shows half-tide.

The sand formation extends from the edge of the water outward with a very gentle slope, and thus makes shoal water for a considerable distance beyond the mass of loose rock seen on the extreme left. With the exception of the barrier ridge, the beach extends laterally for a distance of one hundred and seventy-five to two hundred feet between the solid ledges shown in the photograph. The general constitution of the shore along the river front is solid ledge, and this particular locality may be described as a pocket which has become filled with


  1. N. S., Vol. XXII., pp. 794-796. 1905.