At Napa a few bull-headed oaks come down almost to the tide-line, and in Sonoma a clump of alien blue gums huddles aloof and unregarded, but from the water little is visible beside the stilted cabins of some gun club or the ramshackle resorts of the flat-nosed, slow craft that wind on mysterious errands between the sunken lands. Whole families of half-amphibious humans appear to live comfortably on these drifting scows, but one never by any chance catches them doing any distinctive thing. The waters of the sloughs come down from the little inland valleys, where summer nests and broods in a blue haze along the redwood-serried hills. Whether it is white with cherry bloom at Napa, or purple with winy clusters at Sonoma, there is always something interesting going on there of the large process by which granite mountains are made food for man. It is worth a visit if only to learn that a country which does that sort of thing supremely well, finds it also worth while to do it beautifully. Yachting off San Rafael, it is possible to catch at times the scent of roses on an off-shore wind above the salt smell of the marshes. The last rip of the tide is through the Straits of Carquinez into the back-water of Suisun. From here on, it is a rhythmic heaving to and fro as of well-matched wrestlers, the river-water is set back to Crow's Landing on the San Joaquin, and miles above Sacramento it returns again past Antioch and the Suisun islands. It is lost in a wilderness of tules, through which the sluggish currents blindly wind. Here we have nothing to do with men, our business is all with the tribe of the Little Duck: mallard, teal, tern, coot, heron, eared grebe, and awkward loon. The tule is a round leafless reed. It springs up along the tide-lands or in the stagnant back-water of the rivers, or by any least dribble of a desert spring. No condition daunts it but absolute dearth of water; far-called, it travels on the wind over mountain ranges, over great wastes of waterless plain to find the one absolute condition, a pool--white rimmed with alkali or poisonous green with arsenic. I have seen it flourish by springs so charged with mineral that each slender column is ringed with its stony deposit, but I do not recall any standing water where tules are not. The stems are filled with papery pith so light that the Indians of the San Joaquin made boats of bundles of them, faggoted together and tied upon a wooden frame. Year by year the tules reclaim the muddy confluence of the twin rivers. They make an annual growth, die palely, and are beaten down by the wind; between their matted stems the young green comes up again. In the Land of the Little Duck, miles upon miles of them, and not one other thing, stand up on either side the winding water-lanes, man-high and impenetrable.