Third.-Marking the time which elapses until the water reaches. the boiling point.

Fourth.-Noting how long the water is kept boiling by the different kinds of charcoal.

Before starting the experiments a fire must be lighted in the stove, and both it and the kettle thoroughly heated, so as to give each kind of charcoal an equal chance. When the experiments are proceeding, the fire can be lighted each time by a few bits of live charcoal from the preceding fire, being very careful to select them of equal size in each instance. When the water stops boiling, the stove must each time be cleared of all ashes. By such a process as I have described the figures given in the following table were obtained:

The result obtained from privet was so remarkable that we repeated the trial, which only proved the high heating power of charcoal made from it, the result of the second trial being identical with the first. The charcoal produced in a retort was found to be

superior to that made in an old-fashioned kiln, as will be observed from the result given in the table. The two samples of ash which were selected for experiment were carefully tested to prove this point.-Timber Trades Journal.

V

A CHEAP AND ABUNDANT SUBSTITUTE FOR GUTTA-PERCHA.-A very important discovery is reported from Goa, writes a correspondent. From what can be gathered from a pamphlet issued by Mr. B. F. da Costa, a gentleman well-known in Portuguese scientific circles, he claims to have discovered in the milk of Nivol Cantem (Euphorbia neriifolia) an admirable substitute for guttapercha. The plant is abundant, grows wild in the Concan districts, and is generally used for hedges. Mr. da Costa, in describing its qualities, says that it is insoluble in water, it softens under heat and hardens in the cold. It receives and retains a given moulded shape, can be cast into very thin sheets, and is capable of receiving the minutest impressions on its surface. It is liable to become sticky if exposed to the sun. In its dried state, it is of a chocolate colour. In fact, it has all the properties of gutta-percha. In the Industrial Exhibition now being held in Goa, Mr. da Costa exhibits some nine articles made from this substance, which should, we think, awaken the dormant commercial instincts of the Goanese. Mr. da Costa's procedure in its manufacture is of the simplest. After obtaining the milk by sharp incisions in the plant, he exposes the milk in pans to the action of the air. After the liquid begins to curdle and forms into a hard mass, it is strained through a piece of thick cloth. By this means the water is ejected, leaving a solid white cake, which is gutta-percha. washed with hot water, which removes any milk remaining and facilitates the removal of all impurities from the mass. Insignificant as this discovery may appear, it might be the means of creating a large industry in a country that has hardly any. Mr. da Costa has called the attention of his countrymen to the preparation of kath, or terra japonica, from the Areca Catechu. This is obtained by boiling betel-nut. The boiling water after a time can be condensed, and the mass formed is what in European commerce is known as Areca catechu, or kath of areca. Though the Goanese boil large quantities of betel-nut for a certain class of trade every year, the idea of utilizing the boiling water had not occurred to any one, and Mr. da Costa adds another item by which his countrymen can gain an honest penny.-Times of India.

Finally it is

BREAD FROM WOOD.-A startling proposition has been made by Herr Victor Meyer. In an address recently delivered by him at Heidelberg, it is announced that we may reasonably hope that chemistry will teach us to make the fibre of wood the source of human food. If this becomes possible, an enormous stock of food will be found in the wood of our forests, or even in grass or straw. The fibre of wood consists essentially of cellulose. Can this be made to change into starch? Starch has exactly the same percentage of composition, but it differs very much in its properties, and the nature of its molecule is probably much more complex. Cellulose is of little or no dietetic value, and it is not altered, like starch, in boiling water. It really gives glucose when treated with strong sulphuric acid, as is easily shown when cotton-wool, which is practically pure cellulose, is merely immersed in it. Starch gives the same product when boiled with weak acid. The author further quotes the researches of Hellrigel, which goes to show beyond dispute that certain plants transform atmospheric nitrogen into albumen and that this process can be improved by suitable treatment.-Iron.

CHEAP SUBSTITUTE FOR TEA.-A new industry has sprung up in Germany with the young leaves of the wild strawberry plant. Having been carefully dried, they are used instead of Chinese tea, and are said to approach that beverage very closely in taste. An addition of young bramble and woodruff leaves is said to add to the excellent flavour of this most inexpensive of teas.

THE CHOHS OF HOSHIARPUR AGAIN!-Mountain streams, called by the natives chohs, are a curious cause of destruction of land in the Hoshiarpur district of the Punjab. A collection of papers of different dates, published with Captain Montgomery's Settlement report, gives a vivid idea of the ruin brought upon village after village by the insidious operation of these chohs. The district is characterized by vast tracts of sand, which is spread over the fertile lands by the action of the water, and renders them valueless. One choh is like its fellows, in that it rises far up in the hills below the. watershed, leaves them by a comparatively narrow outlet, and rapidly widens as it makes its way through the plains villages until it breaks up into a number of separate branches. For several years before the sand of a choh reaches a village, the land is enriched by a deposit of extraordinary fertility composed partly of clayey par

ticles washed down from the hills, but mainly of the debris of good lands destroyed in villages higher up the course of the torrent. The village profits most just before the damage by sand begins; so that there is a saying that a choh is gold in front and brass behind. Many villages continue to benefit by chohs in this way for years; some have done so for 40 or 50, but the eventual loss is almost certain, unless the course of the choh is changed higher up; and once destroyed, it may be taken as an accepted fact that the land will never entirely recover its original fertility. No fewer than 914 villages, which were once in a condition of prosperity, have been more or less affected by chohs; or, as another estimate puts it, 30,000 acres of richly fertile and long cultivated land have been laid waste in the last thirty years. Repeated efforts have been made to check the ruinous drifting of the sand, but with small success. The natural growth of trees and scrub would accomplish the object, were it not for the suicidal action of the woodcutters and also of shepherds who allow thousands of goats to browse on the choh lands; while no response is made to offers of Government to reward men who plant trees on the wasted lands. An artificial embankment, consisting of piles intertwined with brush-wood, was washed away after two seasons; and a masonry weir head, constructed at a cost of nearly Rs. 9,000, gave way before a very heavy flood. Verbum sap., but the Punjab rulers are not wise in their generation.

TURPENTINE AND BACTERIA.-Probably for the reason that it is so common and cheap, turpentine is not held in such high esteem as a medicinal agent as it ought to be. It is possible that ninetenths of our stock owners are not aware that, as a disinfectant and preventive of disease, turpentine is one of the most valuable agents known to us-in many respects superior to eucalyptus oil, for the reason that it is more diffusive, especially when taken into the animal economy. A drop in the hand will, in a very short time, be felt in the breath, and if the spirit of turpentine is placed in an open vessel in a room, it will flavour the atmosphere, and when inhaled will be felt throughout the system. In many diseases caused by bacteria or sporules, such, for instance, as blackleg in cattle, any agent that can be absorbed by the system and is fatal to microbe life must, to a certain extent, be prophylactic. Now it is a well-known fact that, among others, turpentine prevents the growth of bacteria in substances in which the spores are otherwise easily cultivable. Thus the microbes of several diseases

are readily cultivable in sterilized broth made from agar-agar, gelatine, and similar substances. If, however, a drop of turpentine is added to this broth, the growth of the bacteria is prevented. A writer in the Mark Lane Express suggests that both turpentine and oil of peppermint might be used as a preventive, if not as a cure, for pleuro-pneumonia ; but, in order that it be absorbed by the system in sufficient quantity, it is essential that it be taken-in minute quantities-in the food. This would be utterly impossible with ordinary cattle, but the experiment might be made with valuable stud cattle that are stabled or fed by hand. But as a disinfectant it is not essential that it be introduced into the system by the alimentary canal. It is sufficient that it be breathed through the atmosphere. Indeed, when administered through the food, the excreta and breath of the animals to whom it is administered becomes a medium of disinfection. The late Dr. Moffat, of Sydney, who for many years enjoyed an extensive practice in that city, found turpentine a most valuable agent in the treatment of typhoid fever.-Indian Agriculturist.

CREOSOTING SLEEPERS.-The practice of the Eastern Railway Company of France in creosoting sleepers is described in a recent issue of the Revue Generale des Chemins de Fer. Sleepers as delivered are stacked and seasoned in the open air. They are then adzed and bored by a special machine, loaded on trucks, and run into a drying oven, where they remain twenty-four hours or more. After drying at a temperature of about 176° Fahr., they are run into a metal cylinder 6 feet 3 inches in diameter and 36 feet long, which is hermetically closed. The air is then exhausted, and a partial vacuum is maintained for about half an hour. Communication is then opened with reservoirs of dead oil, which is allowed to flow in at a temperature of 176° Fahr. under pressure. When the oil ceases to flow under moderate pressure it is forced in by a pump up to a pressure of 83 lbs. per square inch, and this pressure is maintained for an hour or an hour and a quarter. Communication with the oil reservoirs is then opened again, and the excess of oil not absorbed by the timber, flows back into the reservoir. The cylinders hold 168 sleepers each. The quantity of oil absorbed is measured by determining the difference in volume of the oil before and after operation. The wood used is principally oak and beech. The oak sleepers absorb from 24 to 2-7 quarts per cubic foot; beech sleepers from 8.7 to 10 quarts per cubic foot. The whole operation takes about four hours. This method of