portion of the light is wasted. M. Cleman- dot aims by his process to make all the light available for illuiuination. It is based on the principle which governs the diffusion of the light of the sun. This is effected by va- pors floating between us and the sun, which distribute the light equally without stopping more than a very small proportion of it. To imitate these vapors he uses a solid sub- stance, but in a condition so attenuated as to be, for practical purposes, almost the same as vaporous. It is glass, spun into threads one hundred and seventy-five times finer than a hair, or forty-five times finer than the finest silk fiber, with which he surrounds the light with a double envelope. His glass-fleeces are put into a lantern constructed especially for the purpose, so as to exclude dust, the glasses of which may be given any desired degree of opacity, and any color, including those colors which will neutralize the injuri- ous properties of the electric light. The ap- paratus can be adapted to any of the sys- tems of electrical lighting.
William Lassell. William Lassell, LL. D., F. R. S., the famous astronomer and maker of telescopes, died October 5th, in the eighty-second year of his age. His name is closely associated with the history of the reflecting telescope. About 1820, not having sufficient means to enable him to buy expensive instruments, he began to con- struct reflecting telescopes for himself, be- ginning with a Newtonian and a Gregorian telescope of seven-inch aperture, with which be succeeded so well that he was encouraged to make a Newtonian instrument of nine- inch aperture. In 1844 he began an in- strument of two feet aperture and twenty feet focal length, in the making of which he introduced many improvements over the similar instrument of the Earl of Rosse. With this instrument he discovered the sat- ellite of Neptune in 1846, the eighth satel- lite of Saturn, simultaneously with Profess- or Bond, in the United States, in 1848, and two satellites in addition to the two already known, of Uranus, in 1851. He afterward made an instrument of four-feet aperture and thirty-seven feet focus, which he set up at Malta, and with which he made numerous observations of nebulae and planets, be- sides preparing a catalogue of six hundred
new nebula3 discovered at Malta. His latest recorded work was the construction of an improved form of machine for polishing large telescopic mirrors, which is described in the " Transactions of the Royal Society " for 1874.
Climatology of Enrope. The climate of Western Europe is ameliorated by the warmth of the Gulf Stream in winter, and by ihc neighborhood of the ocean in summer, and approaches what is called an insular climate. In Eastern Europe these modify- ing influences cease to be felt, and the cli- mate gradually assumes a continental char- acter, with greater differences of tempera- ture, colder winters and warmer summers. The differences in the summer temperatures of the eastern and western regions are less marked than those in the winter tempera- tures, and amount at most to about 27. For the greater part of the continent the difference in the temperature of July is not more than about 18. The mildest summers are felt in Ireland and Norway, and the hot- test in Southeastern Europe. The differ- ence is perceptible between places in cor- responding latitudes in the southeast and southwest. Thus, Syracuse is 7 and Sebas- topol is 5 j warmer in July than Lisbon and Oporto. A similar difference, but less in extent, appears in going eastward along the northern parallels. The differences in the winter temperatures of the several parts of the continent are much more marked than are those of the summer temperatures. The mildest winters are felt along the Mediter- ranean coast and in the Iberian Peninsula, where the mean temperature in January is from 16 to 19. The next mildest are those of the western coast of France and the southern coast of England and Ireland. The winters of western Scotland and the Orkney and Faroe Islands are milder than those of Berlin and Milan; those of the Arctic coasts of Scandinavia than those of the Gulf of Bothnia, as is shown by the fact that the Arctic fiords of Norway, even as far as North Cape, are not frozen, while the Gulf of Bothnia is regularly frozen in winter. In Russia the January temperature diminishes as we go east, so that, while it is about 24 at Warsaw, it is reduced to 4 at Uralsk. The highest annual mean temperature, the