1. - How To Construct Spirit Lamp. Procure a wide-mouthed bottle, such as is shown in the accompanying figure (d), and fit the mouth with a good stout cork (b); now take out the cork and make a hole through the centre of it, by means of a red-hot wire, but be careful not to make it too large for the tube to be fitted to it. Cut off a piece of brass-tubing, one-quarter of an inch in diameter, and of sufficient length to allow half an inch below the cork and three-quarters of an inch above it. Push the tube in (a) through the hole made in the cork by the red-hot wire, and be sure that it fits well. Pass a piece of cotton used for lamps through the tubing, and be sure that it is long enough to reach the bottom of the bottle. Fit a tin cap (e) to the cork so as to keep the spirit of wine or naphtha from evaporating, and your spirit lamp will be complete.

Practical Science 264 2. - How To Make a Temporary Retort. Procure a Florence flask, such as olive oil is usually sold in, and clean it out by washing the inside well, first with a strong solution of soda and small pieces of brown paper, and then with clean water; turn it up mouth downwards, and let it drain well. Fit the mouth with a sound cork and bore a hole in it with a red hot wire, as directed in section 1. This hole is intended to receive a bent tube, which we will now pro-ceed to form.

3. - How To Construct Bent Tubes for Chemical Experiments. Take a piece of glass tubing one-third of an inch in diameter, and of the proper length - light your spirit lamp (section 1), and hold the tube diagonally in the flame, taking care to turn it round all the time, and to move it backwards and forwards, bo as to heat about four inches of it in the part where it requires to be bent. When the glass begins to get soft, place the two thumbs against the glass so as to form fulcra, as in the annexed figure, and bend it slowly backwards, - that is, towards your body, until it acquires the proper form. When the tube has been bent into the proper shape, heat each end of it in the flame of the spirit-lamp for a minute, so as to round off the edges.

Practical Science 265 4. - How To Make Evaporating Dishes. Procure a Florence flask, clean it as directed in section 2, and be sure that it is thoroughly dry. Take a triangular file, and slightly scratch the flask with the end of it, then run the point of a piece of heated wire in the required direction. Thus, if passed in the direction d e, or f g, in the annexed figure, you will have deep evaporating dishes; if in the directions a o and b o, you will have shallow ones with tips; if from b to g, you will have a very shallow one for evaporating small samples of fluid. Portions of a Florence flask will be quite as useful, or remnants of retorts, which may be cut into circular dishes by bending a piece of stout iron wire into the from given in the annexed diagram, fitting it into a wooden handle, and then, making it hot, apply it suddenly to the portion of flask or retort, and then remove it. This will cause the glass to crack in a circular form (See Section 3.)

Practical Science 266Practical Science 267 5. - How To Make a Funnel. Scratch the flask in a line parallel to h (in the figure above), commencing at d, and proceed as directed for making evaporating dishes.