Where the San Leandro turnpike stretches its dusty, hot, and interminable length along the valley, at a point where the heat and dust have become intolerable, the monotonous expanse of wild oats on either side illimitable, and the distant horizon apparently remoter than ever, it suddenly slips between a stunted thicket or hedge of "scrub oaks," which until that moment had been undistinguishable above the long, misty, quivering level of the grain. The thicket rising gradually in height, but with a regular slope whose gradient had been determined by centuries of western trade winds, presently becomes a fair wood of live-oak, and a few hundred yards further at last assumes the aspect of a primeval forest.