Democratic Sentinel, Volume 17, Number 16, Rensselaer, Jasper County, 5 May 1893 — POPULAR SCIENCE NOTES. [ARTICLE]

POPULAR SCIENCE NOTES.

New Two-Color Printing Press.— Mr. F, X. Hooper of Baltimore, Md., has invented a rotary printing press which prints two colors at once from Princeton curved stereotyped plates. The press is the first iu which this double-color printing has been accomplished by the rotary principle. Kept Time for Two Centuries. — For nearly two centuries the clock built by Langley Bradley, in 1703, has been going steadily in the southwestern campanile of St. Paul’s Cathedral. London: but, although the works remain in excellent condition, the authorities ordered its removal, and it has been taken down to make room for a clock of modern construction. People'in the city are asking why this expense should have been incurred, for St. Paul’s clock was one of the few which kept accurate time, and there was apparently no reason why it should not have continued to do so. It was an eight-day clock, and struck the hours and quarters. The pendulum is sixteen feet long, and the bob weighs 18 > pounds, and yet was suspended by a spring scarcely the thickness of a shilling. It cost £3OO. For the present, and probably du'riug the next few weeks, the dock-dials will remain without the minute hands, which are nine feet eiglit inches in length and weigh seventy-five pounds. The hour hands are about four feet shorter.—[London Telegraph.

Colors of the Ocean. —A number of interesting charts, illustrating the colors of the ocean, have been presented to the Paris Museum by Prof. Pouchot, with accompanying explanations. It is well known that M. Pouchot some time ago proved, after extended investigations,that the differences in the color of various parts of the ocean are due to differences in the water itself and not to the presence of vegetation and insects, and the new charts in question confirm this view. It seems that lie and his associate, M. de Curfort, watched together the Atlantic from Spitzbergen to Scotland and the Norwegian coast.and with such thoroughness as to admit of nothing escaping their attention. Their observations show that the transition from one color to another is often very rapid; that near Spitzbergen the water is blue, then it changes to green as soon as the Norwegian fiords are entered. For such sudden changes no sufficient cause has up to the present time been assigned; and, though it has been known for centuries that blue is the prevailing color in active water, the most recently published observations show that such a color distinguishes other localities also. Valuable Results of Experiments Upon Animals. —ln a receut article Sir Andrew Clark gives a brief list of the benefits mankiud have derived from experiments upon animals. He says: ‘‘Bv experimental research we have discovered the conditions for using with efficacy aud safety almost all the stronger and more useful drugs, such as digitalis, chloroform, ether, chloral, nitrate of amyl, ni-tro-glycerine, and many others. By experiments on animals we have discovered the nature and relations of infectious diseases, and how in some measure to control the development and spread of fevers, cholera, anthrax and septicemia. Through experiments on animals [the legsof Galvani'simmortal frogs.-Ed.] we have received the electric telegraph, and all the various services which electricity now renders to the conveniences and uses of mani And yet with all these services before us, one cannot (in England) scratch the neck of a tabbitfor the advancement of knowledge without becoming a legal criminal. But, on the other hand, for your pleasure or for your profit, or for any other object than the promotion of knowledge, you may, without let or hindranoe, beat, starve, mutil ite or destroy as many animals as you C lease. Knowledge can only be advanced y experiment . . . aud lastly, if experimental research hardens the hearts of experimenters it is only too plain that an active antagonism to it begets a disregard of accuracy, a violation of charity, and a spirit of" calumny tint have no parallel among ordinary men.’’—[lndependent.