"Well," said Mr. Grigsby, "gold may be loose in the dirt, or held in rock. The first is a placer, the other is a vein or lode. Nearly all the mining out here is placer mining, where the dirt is dug out and washed away, leaving the gold. But of course the gold in the placer beds must have come out of a vein somewhere above. It doesn't grow like grass. 'Cording to the scientific idee it was melted into the rock, first, like into quartz, and then was worn away by the weather and carried into the dirt. I don't fancy breaking up rock, to get gold, when in a placer it's already been broken for you. But they say quartz mining can be made to pay well, if you have the proper machinery. As like as not this man 'Tom' was waiting for machinery." "Tom." Tom who? And what was his nephew's name? And did his nephew know about the mine? And was he out here looking for it? These and other questions Charley kept putting to himself, because nobody could answer them for him. The main thing now, anyway, was to get off, to the "diggin's." They paid their bill, shouldered their baggage, and wearing their complete miner's costumes (Charley sporting his knife and his belt) they proceeded down to Long Wharf and the _Mary Ann_. On their way they collected their washing from the bowing Frenchman. Long Wharf was the principal wharf, where they had climbed the stairs when landing from the _California_, and was at the foot of Clay Street, just beyond Montgomery, only a few blocks from the plaza of Portsmouth Square. The tide was half in, partially covering the ugly mud-flats, and extending all around the wharf. Considerable of a crowd had collected, on the wharf. They were in flannel shirts and boots and coarse trousers belted about with pistol and knife, and were laden with baggage rolls. Evidently they, too, were off to the mines; perhaps by the _Mary Ann_. "That must be the schooner, out yonder--I can see _Mary Ann_ on her stern," spoke Mr. Grigsby. "And I reckon that's her boat coming in." "I'll get you out quicker'n that, stranger, if you're for the _Mary Ann_," cut in an alert by-stander. "Five dollars for the trip; safety guaranteed." "Not to-day," smiled Mr. Grigsby. A skiff was being pulled in, from a schooner anchored out a short distance. At a nod from Mr. Grigsby, Charley and his father pressed forward with him, to meet the boat at the foot of the long stairs. Yes, it was from the _Mary Ann_; and they and a dozen others (or as many as the boat would hold) tumbled in. The _Mary Ann_ was a small schooner, about fifty feet long and twenty feet wide. She had one little cabin with four rooms, so that the passengers were expected to sleep on deck or in the hold, where bunks had been built along the sides, with the dining table (of boards) in the middle! However, who cared, when they were off to the mines and this was one way to get there? "How long'll it take us, to Sacramento, captain?" hailed one of his passengers.