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tion of this race, which had been too much influenced by accounts he had received from a tribe at war with the cannibals. He had said that in their villages he had found quarters of human flesh exposed for sale; that they killed and ate their prisoners of war, and that they sold the bodies of their own dead who had died of disease to their neighbors. M. de Brazza denied the truth of such accounts. As a proof that the Fans bad kindly and generous sentiments, he told how a Fan chief had been kind to him when he was obliged to leave his people sick in the bush. He owed his life to the Fan chief, and he should always be grateful to him and his people. He wished, therefore, to do all he could to remove the prejudice against the Fans which had been excited by Du Chaillu. They were a very generous, courageous people. It was true they were cannibals—that they ate their prisoners of war; but it was with them a religious idea, for they believed that in eating the heart of a brave man the courage of the dead passed into themselves. M. de Brazza also gave an interesting sketch of the Akkas, a dwarf race he found scattered up and down among the different peoples, like what the Jews or the gypsies were in Europe. The height of the Akkas was from three to four feet.

Raising Sunken Vessel.—In the Plötzen Lake, which is not far from Berlin, and the depth of which is very considerable, reaching in some parts to twenty-eight metres, an interesting attempt has been made to raise sunken vessels. The method, which is the invention of Herr Eidner, a Vienna civil engineer, consists in applying carbonic acid in the following manner: In an empty balloon a bottle half filled with sulphuric acid, surrounded with Bullrich's salt, is fixed; the bottle is destroyed by turning a screw, and the two substances mix and produce carbonic acid, which fills the balloon. It is obvious that, when this apparatus is brought into operation in the hull of a sunken ship, the effect must be, if a sufficient number of balloons are filled, to raise the vessel. In the experiments on the Plötzen Lake, a small vessel or boat weighing several hundred-weight, was first sunk. A diver then went down with the necessary apparatus, which he set in operation in the interior of the ship. Hardly had he done so before the vessel began to rise to the surface, where it was maintained by the balloon. In a second experiment five heavy sacks filled with sand were thrown over-board, in a part of the lake which was sixteen metres deep. The diver descended, fastened all the sacks together, and, fixing the balloon apparatus to them, set it going, with the effect that the whole of the sacks were brought up to the surface.

Petroleum in Iron-making.—The successful employment of petroleum as a fuel in the manufacture of iron, has, according to the "Engineering and Mining Journal," been accomplished by a process invented by Dr. C. J. Eames, and now in practical operation at Titusville, Pennsylvania. The petroleum is vaporized by means of highly heated steam, thrown into a chamber in which the oil is caused to trickle over a series of horizontal shelves; and the mixture is then driven onward to the combustion-chamber, where it is ignited and forced into the furnaces by the air-blasts which it encounters at this point. "The evident advantages," says the "Engineering and Mining Journal," "of petroleum-fuel, are the perfect control under which the heat is held; the extremely high calorific intensity of this 'water-gas'; and the freedom of the fuel from any elements injurious to the iron. It is claimed that the work can be performed much quicker, and the quality of the product can be made much more uniform and of higher grade, than can be secured with coal-fuel."


NOTES.

According to Professor Lintner, President of the Entomological Club, the study of entomology is making very gratifying progress in this country; collections are multiplying, and the literature of the subject is growing rapidly. The Club has compiled a list of persons engaged in the study of entomology in the United States; it already contains eight hundred and thirty-five names.

Dr. Krümmel, of Göttingen, estimates the mean depth of the sea at 1,877 fathoms, and then makes a comparison of the volume of the land above sea-level with the volume of the sea. Accepting Leipoldt's