This machine is a simple trough about nine feet long with a bottom made of cast iron plates perforated throughout, the size of the holes increasing gradually as they descend towards the lower end; beneath these plates there are draws in which mercury is put; the dirt, as the machine keeps rocking slowly, is carried along the plates by the water thrown from above by a pump and washed down, gold together with finer particles of dirt descend into the draws to be amalgamated with mercury. The produce of such a washing is then put into a retort to separate the gold from the mercury. In the process of separation of the former from the latter, about two per cent. only of mercury is lost. These two kinds of machines are the only ones which we can recommend from our own observation; they are well adapted for these mines at least, and they can be easily procured here. Numerous inventions for this purpose were brought from the States, and none of them answered the sanguine expectations of their owners; they are not worth here even the cost of the materials they are made of. The provisions used by the miners consist of mess pork, bacon, hams, jerked beef, flour, sugar, tea, coffee, chocolate, beans, rice and dried apples, fresh beef and mutton whenever they can get it, which is sometimes the case, and deer meat when they can kill it. As much as one can, for the sake of his health, he should abstain from using much salted provisions in the mines, and to counteract their bad effect on the system, it is advisable to use vegetable acids, like lemon juice, which in the mines is sold bottled up; citric acid, which is more easy to carry, or even tartaric acid, dried apples, and other dried fruit serve the same purpose. In using these acids it is better to use them with water alone without sugar; just making it acid enough to suit the individual taste. Dried apples made into apple sauce with sugar are agreeable to take, and are calculated to keep the bowels open, an important consideration for the miner. If one should be attacked with diarrhœa or dysentery of course he should abstain from them. One of the articles equally important as others we have not yet mentioned; we mean saleratus. In making camp bread it is necessary to use it to make the bread lighter. The prices at which provisions can be bought at present in San Francisco are the following: