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ON THE: PLOUGH. 31

This is obvioufly the cafe in the motionof| a fhip of the fharpeft bow; and there can be| no queftion, if the fore-part of a fhip were made in the figure of a wedge, it would meet with lefs refiftence than in any curved figure of which it can be formed. But fuch a fhip would be altogether unfit for the pur- pofes of navigation; for fhe could bear very little fail, and the leaft hard gale would run her down.‘This is the reafon why hips with the broadeft bows are the fafeft, though the worft failers.

The refiftence made to the plain figure will be ftill proportionally lefs in moving through fuch a body as earth, whofe parti- cles have a confiderable fri@ion and cohe- fion.. The curved figure, in this cafe, be- fides pufhing the particles before it, muft+ be expofed to more frition, as its furface is larger; for it is evident that the leaft curve Ny muft make the furface greater than if it were plain.

Tolprove experimentally what has been ad- vanced, I procured ahalf-wedge of the fame greateft breadth with thofe formerly men- tioned, but rifing on the right fide with a

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