African Trade attracts much attention in English commercial circles at present. It is intended to establish one or more lines of steamers to ply between England and the African coast, to be engaged in the traffic in palm oil, etc. For this purpose it is proposed to use the newly invented iron casks as a substitute for wooden ones, by which means the necessity ot having coopers with each steamer would be obviated. Iron casks will, it is said, be cheaper and more durable than wooden ones, besides being more portable as they may be taken apart and set up again by any person, and when not set up, 'Yill occupy but a small apace. Well Sinking—Artesian Wells. (Continued from page 88 ) Boring—In our last article on this subject' we presented two illustrations of the geological character of a country, where the boring for water to overflow the rim of the well would be successful. We will now present an illustration of some of the tools employed. When the mouth of the spring is scooped out, it is built around with well cemented bricks to keep out surface water, or by employing iron cylinders, or any suitable method, such as a bored log of timber, as mentioned in our last article on the subject. The simplest me thod of boring is called the “ Chinese System.” All the rods ordinarily connected with the boring tool, are dispensed with ; and the bo rer is suspended by a rope, which, when the tool is lifted vertically and let down, it imparts, by its torsion, a sufficient circular motion to it. In this engraving, a, in fig. 1, is a tool surrounded by an iion cylinder ; the products of the excavation become collected in the circular space between the tool and the cylinder, by which means, they may be brought up to the surface. With this simple machine—various tools being used for different strata—it may be asked why this plan is 11 J Q 5 I (Q) PT EL c p) ill to 9 rrV) rfl-. , 10 not generally used 1 The fact is, it is liable to bore a crooked hole by the twisting action of the rope ; therefore, the ordinary plan is to attach iron rods to the borer, which are in lengths from ten to twenty feet, and screw into one another; a circular motion is given to the tool by the workmen above, but the iron rods have all to be unscrewed, when the products of boring are drawn up. When an Artesian well is to be bored, a flooring is laid with the hole in the centre, and wooden trunks or iron pipes are fixed as guides for the tools. As the hole is bored, permanent pipe is inserted, which are either of wrought or cast iron; figs. 2, 3, and 4 show lengths of these pipes. The collars of the pipes are generally screwed together. Wrought-iron pipes are seldom rivet- ted ; they have their collars soldered on them. The solder is run in and melted in the pipes by suspending an iron heater, (figs. 5 and 6) down the pipe ; the small heater is made of one, and the large one of two circular pieces of iron. The pipes are slung down the well by means of a wooden plug (fig. 7), which has a pin or key passing through it ; this is inserted into the end of the pipe, which is cut reversely in fig. 8, and can easily be withdrawn. The boring rods are usually turned round by the leverage of two handles (figs. 9 and 10). Where the work is too heavy for manual power by these levers, horse or steam power may be employed. The rods for boring are shown connected in fig. 11. A circular and vertical percussive motion is given to the tool; various plans have been employed to give the tool an easy rotary motion along with a vertical motion, to act upon the rock. The spring spiral motion, shown on page 40, this volume of the Scientific American, the invention of J. Thomson, of Philadelphia, is no doubt the most simple yet introduced. Various plans for giving the borer its proper motion have been brought forward ; there is one of Messrs. Wightman&Vaughan, illustrated on page 132, Vol. 3, Scientific American ; one on page 1S3, same volume, by Foster&Bailey ; and there is one on page 137, Vol. 5, with improved tools—a foreign invention and well worthy of attention. We do not present these machines again, but merely refer to them as positive information already published in our columns. In putting down pipes, of course the judgment of the operators must decide, according to locality and the nature of the strata, how this can be done in the cheapest and best man ner. (To be continued.)