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A correspondent of the Building JVews recommends the piling of floor boards as illustrated in the accompanying diagram. Four long poles are planted in the ground, and the boards are placed at an angle against them as shown. By planting posts at short intervalle "between the corners many more boards can be stacked in the same space. This method gives a much freer circulation of air than the ordinary method, find consequently the drying proceeds with greater rapidity. Soiid and Electric Figures. ' What are termed sound figures may be produced in various ways. One way is to fix a plate of glass at its center with Burgundy pitch to an upright support on a stand, then to dust the plate with fine dry sand or other suitable powder, such as lycopodium. If now the plate be made to vibrate by drawing over its edge a violin bow, or some horse-hair tightly stretched from the two ends of a cane well rosined, the dust will in due time arrange itself into certain forms, lines, or figures. The same will occur by tying over a broad-mouthed glass or goblet with bladder that has been moistened and allowed to dry to a drum-like surface, and dusted with lycopodium or very fine sand, and then put upon a piano. Certain lines are soon visible after the instrument has been played upon, particularly when one chord only has been struck, so as to lessen the vibration. The blowing of a cornet, using one key, or the tuning of one note of any instrument, near the stretched membrane, will cause it to vibrate, and the dust to arrange itself into form. Thus these experiments clearly exhibit the effects of sound ; and by due study of the dust lines we may see what sound, one long passed, has been. A somewhat similar application of this experiment has recently been made by a German philosopher to the study oi the na-tureof electrical discharges between metallic conductors. It is found that when an electric discharge takes place between a horizontal plate of metal powdered with lycopodium, form-iig the positive pole, and a ball or point placed below it, the dust remains attached to the plate on a well-determined area.— e'ptimus Piesse. inrv mutt' Csood ider Vinegar, Take ten gallons of apple juice fresh from the press, and sufier it to ferment fully, which may be in about two weeks, or sooner if the weather is varm ; and then add eight gallons like juice, new, for producing a second fermentation ; in two weeks more add another like new quantity, for producing a third fermentation. This third fermentation is material. Now stop the bunghole with an empty bottle, with the neck downward, and expose it to tbe sun for some time. When the vinegar is come, draw off one half into a vinegar cask, and set it in a cool place above ground, for use when clear. With the other half in the first cask, proceed to make more vinegar in the same way. Thus one cask is to make in, the other to use from. When making the vinegar, let there be a moderate degree of heat, and free access of external air.
