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It is reported that McCullogh peak, the volcanic mountain which was described and pictured in the SCIENTIFIC AMERICAN of October 26 last, has prac tically vanished. Thrown up to a height of more than 3,000 feet by volcanic activity, it has now sunk until it barely rises above water. It is believed that the subsidence was a sudden one, due to an earthquake. Archaeologists have long believed that if Herculaneum could be uncovered, it would yield treasures more perfect and more valuable than those of Pompeii. But the cost of excavation, which would be much heavier than that of uncovering Pompeii, has always been a deterrent. Public interest in Europe has re cently been directed to the suggestion, and as a result Signor Rava, the Minister of Public Instruction in Italy, upon whom the work actually depends, has pre pared a bill providing for an appropriation of $100,000, for the purpose of removing the houses forming the modern town of R sina, which is located over Her-culaneum, and an appropriation of $3,000 a year for actual excavation work. This at least insures Italy's practical interest, and brings the excavation appre ciably nearer. The famous "Giants' Causeway" in the north of Ire land is suffering the fate of the New Jersey palisades overlooking the Hudson, for it is in the hands of stone merchants. A consignment of 200 tons of the basaltic columns comprising the Causeway has recently been shipped to Philadelphia. It. will be asked whether there is no power in Ireland to protect the Causeway. Although at one time it was supposed to be the work of the giants who abounded in Ireland, and to whom a piece of construction about a furlong in length would be child's play, it is not in a legal sense an ancient monument. The Irish courts decided that the stones belonged to a company, and since that time the cause way or pier cannot be seen without payment. It may therefore be assumed that the disposal of the basalt is a legal transaction. America is fast becoming a great museum, and it will be incomplete unless several of the natural as well as the artistic "curiosities" of Europe are to be found here. M. Gustave Lippmann, the eminent scientist, recently made an experiment which gave some new results in connection with osmotic action. This relates to the endosmose of two liquids which have the same chemi cal composition but are used at different temperatures. It is already established that endosmose takes place between two liquids of different composition, such as pure water and a sugar solution. He wished to find whether there is any such action between two masses of the same liquid having different temperatures, and observed that such is the case. Two masses of pure water, one hot and the other cold, were separated by a porous membrane. There was found to be endos mose of the cold water toward the hot. As he could not use the ordinary kind of measuring instruments in this case, seeing that the action of heat would af fect them, he devised a special instrument. The mass of liquid to be heated is contained in a narrow space between a porous disk about two inches in diameter and a brass disk lying opposite it. A thin rubber ring separates the disks, which are pressed together. A thin layer of the liquid is thus formed which is about one-fiftieth inch thick and has but a small volume. By means of a small brass tube the space is filled with hot water, and the tube is joined to a second hori zontal tube of graduated glass. A cold water chamber is made in the same way, using the second face of the porous disk and a corresponding brass disk, filling the space with cold water by means of a second tube which is in permanent connection with a cold water tank. To give the difference of temperature between the two liquid layers separated by the porous uisk we place the first brass disk upon a vessel of boiling water, so that it is in contact with the steam. At the same time the upper brass disk serves as the bottom of a vessel in which cold water circulates- by a tube com ing from the water pipes. In a few minutes there is established a constant difference of temperature. After waiting for half an hour we observe the osmotic action to be quite marked and regular, using gelatine as the membrane, the graduated glass tube filling up with water. The liquid column is increased at the rate of 0.6 inch per minute, and when the tube is full, the water comes out from the end. In a few hours the water which comes out has five or six times the volume of the hot chamber, and therefore the action is not due to heat expansion. Insoluble gelatine is found to be the best membrane for this purpose, but cellu loid and other material can be used. Instead of measuring the volume of water we can also find the pressure or suction. The pressure is taken by placing the graduated tube in the vertical position. There is found to be pressure or suction according as the manometer gage is connected with the hot or the cold water chamber. Gases show a similar action, and the experiment can be made with hot and cold air and a paper membrane, and is easy to observe, as it is more rapid than with liquids.
