112 ALFRED W. G. WILSON 



that we find that the efficient wave and wave-current work in 

 shore transportation is done by those winds whose direction con- 

 forms nearly with the axial direction of the several sections of 

 the bay. The narrowness of the bay, coupled with the depth of 

 the valley, is such that even violent storms blowing across it can 

 do less efficient work than is done by the much gentler local 

 breezes blowing up or down the bay. 



In this locality the prevailing direction of the wind during 

 the summer is from the southwest ; but, in spite of this, it is 

 found that, because of the considerations to be noted below, 

 there is virtually no continuous- transportation eastward except 

 along parts of the lower portion below the Upper Gap. There 

 ■seems rather to be a constant oscillation to and fro. Because of 

 the shape of the bay and its position the directions from which 

 efficient winds and their accompanying waves can come are the 

 northeast and the southwest. 



The material which forms the forelands varies from fine 

 sand in one example to large rock plates weighing over four 

 pounds each. All the spits but one are built of coarse and fine 

 gravel or shingle. In most cases the material is almost all so 

 coarse that its transportation must be attributed to the wave 

 itself, rather than to the action of any longshore current during 

 the intervals that the wave may have raised it off the bottom, 

 though no doubt these currents assist in that transportation to a 

 small extent. It is moved in part by rolling along the bottom, 

 but even some of the largest fragments are frequently lifted clear 

 of the bottom and carried along with the wave. The shape of 

 the oblong or rhomboidal plates (rarely over an inch thick, 

 and with an area on the flat side, varying from ten to thirty 

 square inches) materially facilitates this mode of transportation. 



THE FORELANDS AND BARS. 



I. Sand Spit below Bogarf s dock. — This is a small spit which 

 consists wholly of fine sands derived from the adjacent cliff cut 

 in modified drift. The spit measures about 245 feet across the 

 base and extends about lOO feet out from the shore line. The 

 normal width of the beach between the cliff front and the water 



