obviating the greater part of the heat by first engaging the glycerine in a combination with sulphuric acid, which forms a sulpho-glyceric acid, and then destroying this compound slowly by means of nitric acid. Two liquors are prepared in advance—a sulpho-glyceric and a sulpho-nitric liquor (the latter with equal weights of sulphuric and nitric acids). These disengage a considerable amount of heat; they are allowed to cool, and are then combined in such proportions that the reaction takes place slowly. In the old method the nitro-glycerine is separated almost instantaneously, and rises in part to the surface, rendering washing difficult; in the new method it forms in about twenty hours, with a regularity which prevents danger, and goes to the bottom of the vessel, so that it can be washed rapidly. In the works of Messrs. Boutmy and Toucher at Vouges, where the new process has been employed, no life has been lost for six years, and the general health has been excellent.
The annual meeting of the National Academy of Sciences was held in Washington, D.C., beginning April 19th, under the presidency of Professor W. B. Rogers, of Boston, The sessions continued through four days, and were marked by the reading of a large number of papers, of general as well as special interest. None of the papers received more attention than that of Professor Bell concerning his later experiments in the production of sound by radiant energy, which we publish. Professor Barker, in his paper on "Incandescent Lighting," also touched a subject which engages general interest. The papers of Professor Pumpelly, on the relation of soils to health, of Professor Morse, on the utilization of the sun's rays in heating and ventilating, and others, show that the Academy does not neglect practical subjects. Mr. W. H. Ball gave an account of the "Land Ice in Kotzebue Sound," of which mention has already been made in the "Monthly"; and Professor T. Sterry Hunt described the "Auriferous Gravels of California." President Garfield visited the Academy, and was warmly welcomed. The meeting was more than ordinarily interesting.
The Boston Society of Natural History announces that a seaside laboratory, capable of accommodating only a limited number of students, will be open under the direction of its curator, Alpheus Hyatt, at Annisquam, near Gloucester, Massachusetts, from June 5th to September 15th. As the purpose is simply to afford opportunities for the study and observation of common types of marine animals under suitable direction and advice, no attempt will be made to give any stated course of instruction or lectures. The work will be adapted to meet the wants of those who have already made a beginning in the study of natural history. The apparatus will consist of the simplest laboratory furniture, collecting instruments, and row-boats, and a yacht for dredging excursions after the latter part of July.
Achille Delesse, an eminent French geologist, died March 24th. He was engaged through most of his life as a mining engineer, and was at one time Professor of Geology and Mineralogy at Besançon, and at another Professor of Agriculture, Drainage, and Irrigation in the École des Mines. He was author of works on some of the mineralogical features of the Vosges, of "Researches on the Origin of the Rocks," geological and hydrological maps of the city of Paris, and the rainfall of Paris, and, in conjunction with MM. Langel and De Lapparent, issued for twenty years the annual "Revue de Géologie." He was for two years President of the Geological Society of France.
"Nature" doubts whether our Fish Commissioners will be able greatly to increase the yield of sea-fish, like shad, herring, and cod. The arguments of Malthus respecting the relations between food-supply and the increase of population are thought in England to be applicable to fish. "Sea-fish, like all other animals," it says, "are undoubtedly increasing in greater proportion than their food; and it is obvious, therefore, that, unless man can increase their food, it is only lost labor to increase their number."
Fanny, a very aged carp in the ponds at Fontainebleau, well known to the people of Paris, has just died. She is said to have been hatched during the reign of King Francis I, and had become very gray.
The sixth session of the Summer School of Biology of the Peabody Academy of Science, Salem, Massachusetts, will commence July 12th, and continue for four weeks. Instruction designed especially for teachers. Further information may be obtained from Professor Edward S. Morse, of Salem.
Mr. William Pearce, of the Clyde ship-building firm of John Elder & Co., has stated, in a lecture on recent improvements in marine navigation, that the first steamers of the Cunard Company, in 1840, were under contract to go 812 knots an hour; were of 740 horse-power; and consumed 4710 pounds
