22 THE ANALYST, APPARATUS. A Self-Igniting Bunsen. H. Schimmel. (Chern. Zeit., 1903, xxvii., 1037.)- This is a Bunsen fitted at its base with a two-way cock, from which a by-pass tube rises to a short distance below the orifice of the burner, where it carries a small ball of platinum black. When the crank handle of the cock is at one end of its limited travel, the gas is entirely shut off; when the handle is moved to its intermediate position, gas is admitted to the by-pass, and is inflamed by the platinum ; and when the crank is thrown right over, the by-pass is cut out and the main supply turned on, A sloping hood, supported by the large tube, protects the platinum black and the by- pass tube from any liquids which may be spilt. The apparatus is patented in Germany, the maker being J.Schober, of Berlin. F. H. L. A Reading Device for Burettes, etc. H. Gockel. (Chem. Zed., 1903, xxvii., 1036.)-The annexed diagrams represent a simple reading device for burettes, which not only renders it easier to view the critical edge of the liquid meniscus accurately, but also avoids all errors caused by parallax. It consists of a pinch-clamp, the jaws of which are so cut that it will fit vessels of different diameter, yet, provided the vessel is vertical, will always attach itself in a truly horizontal plane. Thus, if the eye is so placed that the axis of vision is parallel to the top or bottom of the apparatus, the burette must be read normally. The clip is applied to the burette with its upper I ? 11 Ha' Men ii CIU § surface 2 or 3 millimetres below the lowest part of a concave meniscus, or with its lower surface 2 or 3 millimetres above the highest curve of a convex meniscus ; and in this position it cuts off superfluous light, so that the height of the liquid may be ascertained more exactly.If the volume of 0.1 C.C. occupies a space of 1 millimetre in the tube, it is claimed for this instrument that a reading may be made to 0.01, or even 0.005 C.C. The apparatus can be obtained from Sauer and Gockel, of Berlin. F. H. L.THE ANALYST. 23 Some New Apparatus. A. Waeg- ner. (Oesterr. Chem. Zeit., 1903, vi., 409.)-A CO, Apparatus.-This consists of a pear-shaped flask K fitted with a, rubber cork having two holes. Through one passes a tube D to the bottom of the vessel, where it is narrowed and curved upwards slightly ; this serves for the final admission of air, and is closed during the decomposition by a clamped rubber tube.Through the other hole passes a three-way tube C, cut off obliquely just within the flask, through which is placed a glass rod G with a hook at its lower end to carry the vessel H holding the carbonate. This rod travels air-tight through a rubber sleeve at the top of the T-piece, and is pushed downwards gradually as decomposition proceeds. The lateral aperture of the three-way tube bends upwards and becomes a long vertical tube A 12 millimetres in diameter, which is packed with glass balls. To its top is joined an inverted U, which connects it to a similar descending tube B, three - quarters filled with - I calcium chloride, and charged with E copper sulphate pumice beneath.The exit of the latter tube leads to the absorption vessel for the carbon dioxide, which may be either a potash apparatus holding the carbonate has a small lateral hole near its base for the entry of the decomposing acid; this hole is covered with glass-wool. Apparatus f o r Filtrations with the Gooch CrucibEe.-This consists of a pear- shaped separating funnel ,with a twice- bored rubber cork. One hole carries a tube funnel in which the crucible is placed and made tight with the usual rubber washer. The other bears a, bent FiS f or a tube of soda-lime. The tube H L three-way tube, one limb terminating in a stopcock, the other passing to the24 THE ANALYST. pump. By this arrangement, when some liquid has been collected and found to contain asbestos fibre or to be otherwise turbid, the vacuum in the funnel is broken by opening the stopcock mentioned, and the filtrate is run out of the separating funnel through the stopcock at its base.Condensation in Organic Combustion- Tubes.-To prevent this trouble, a sleeve of silver foil is put round the projecting part of the tube so as to extend about 1 centi- metre into the furnace and to about 2 millimetres short of the cork. The high heat- conducting power of the metal keeps the temperature in the tube at a sufficient point to avoid condensation without injuring the rubber stopper. F. H. L. - -. . - ___ _____ ._ Gas Furnace for the Laboratory. IC. Friedrich. (Zeits. f. angew. Chem., 1903, xxxvi., 857.)-The furnace is so constructed that several kilogrammes of material can be treated at one time, and the flame can be so regulated as to produce the same effects as are obtained on the large scale.The body of the furnace rests on an iron plate b, supported by four columns a, and is held together by the iron casing A , in which there are a number of openings. I The The GKOUND PLAS. 700 0 7UU 200 300 900 M~~ 1 t - , hearth B is supported upon a separate plate p , which is held up by the bars ma. level of the hearth can be adjusted by means of the wedges n. The air and gas are introduced through the two openings cl, c2, which are inclined towards each other. The gases inside the furnace are caused to rnix'thoroughly by striking the opposite wall. They then pass out through the opening d and up the vertical flue E, which is lined with fire-clay.The fused material can be run off through the channel K, or can*be drawn along the gutters rl r2 into the holes ql q2, below which receptacles can be placed to receive it. The two There are two working doors, fl and f2.THE ANALYST. 25 burners D each have aeven jets, the upper five of which are controlled by common taps, whereas for the lower two there is a separate tap for the gas and another for the air. By adjusting these taps it is possible not only to regulate the temperature, but also to produce either an oxidizing or reducing atmosphere immediately over the work. The conditions in the furnace can further be varied-by placing wedges of clay in the openings cl, c2 and d, by raiaing or lowering the hearth B, and by pushing in or out the fire-clay damper 2.The hearth can be removed and replaced by one of EI different shape or of another material. The roof C can also be taken off, SO as to allow repairs to be executed. Using coal-gas and air at a pressure of 200 millimetres of mercury, the temperature rose in ten minutes to 1,195" C., and in a hundred minutes to 1,420' C. A higher temperature could be obtained by replacing part or all of the air by oxygen. Some improvements (ibid., 1077) have been made in the furnace previously described. An arrangement has been introduced for raising and lowering the hearth by means of a screw and hand-wheel. The lid of the furnace also has been lightened, and an aperture has been made in it for the introduction of a pyrometer." Issem " burners have been substituted for those used originally, but they are arranged as before, two on each side one above the other. These render it possible to attain a higher temperature: in ninety minutes this rose to 1600' C., although a more powerful fan than the one used might have been advantageous. The apparatus is manufactured by Karl Issem, Berlin-Reinickendorf. A. M. Carbon Dioxide Apparatus for Use in Damp Air. A. C. Kuyt. (Chem. Zeit., 1903, xxvii., 1086.)-The author states that errors of from 3 to 9 per cent. in the estimation of carbon dioxide with the aid of the Geissler apparatus are not uncommon in the tropics, where the atmosphere is so highly saturated with moisture. He has therefore added to the usual form of apparatus extra drying-tubes, as shown by the annexed illustration. A and C are charged with calcium chloride ; when the apparatus is being weighed, their places are taken by the stoppers, D and B. The tube, B, contains soda-lime. The air which enters when the strong hydrochloric acid in G is allowed to run down into the flask is freed from moisture by C, while any acid vapours that may arise are caught by B. The tube, B, similarly protects the sulphuric acid in D from the moisture of the atmosphere. The apparatus is made by Geissler (Miiller), of Bonn. F. H. L.