[Entered at the Post Office of New York, N. Y., flS Second Class Matter. Copyrighted. lA88. by Munn & Co.J A WEEKLY JOURNAL OF PRACTICAL INFORMATION, ART, SCIENCE, MECHANICS, CHEMISTRY, AND MANUFACTURES. A YEAR. [,3.00WEEKLY. THE NEBRASKA CITY PONTOON BRIDGE. bridge begins, and reaches across the main river, with increase the strength of the steel anchoring cables. The We illustrate in the present issue a new bridge re- a length of 1,074 feet. As will be seen from the cut,thE' bows of the boats are to be sheathed with iron and cently completed, which crosses the Missouri River at bridge is angular or V-shaped. The point or apex of the bottoms are to receive an extra planking of oak. Nebraska City, Neb. The bridge is of a type that has the angle points down stream. When it is necessary It is considered certain that the rapid current will but little d for military th draw, the connections under p ed to been use , except purposes. It to open e at the apex are loos­ sweep all obstacles the boats. It is pro os consists of a flooring carried by a !lubstructure which ened and the current at once swings the two members remove the bridge when ice forms on the river. floats upon the river. A similar bridge across the Rhine, apart, leaving an unobstructed channel of 528 feet in The object of arranging the draw in the peculiar between Coblentz and Ehrenbreitstein, will be rernem- width. In this feature it is the largest drawbridge in shape shown was to facilitate closing. The govern­ bered by our readers, where the floor is carried by a the world. When it is desired to close it, the ends of ment, in granting the charter, had stipulated for so series of boats or pontoons. A pontoon bridge is also the draw members are brought together, the current wide an opening that it seemed doubtful if a pontoon THE GREAT PONTOON DRAW BRIDGE OVER THE mISSOURI RIVER, AT NEBRASKA CITY. in. use across the MiSSissippi River at Prairie du Chien. being made to do most of the work. The eutire opera­ could be closed at right angles to the axis of the In military operations pontoon bridges,from their port­ tion can be managed by one man. stream. ability, and on account of the rapidity with which This is in strong contrast to other structures of the Both the pontoon and crib bridges were built within can be ut tog t have acquired much they p e her, import­ same character. The draw in the Prairie du Chien the short space of twenty-eight days, at a cost of about e rly all the important structure alluded to above requires Col. S. ance, and have figured in n a a powerful en­ $18,000. N. Stewart, of Philadelphia, was the wars of modern times. gine to close it. constructing engineer. franchise for tw lv The bridge is divided into dw v c In the ckgr u d is shown a second bridge, built Nebraska City had held a e e years a roa ay for ehi les ba o n for the construction of a pontoon bridge. All move­ and two side paths for foot travelers. The roadway is for the use of the railroads. This also is a recently ments in the direction of carrying on the work met sixteen feet wide. On one side is a three-foot sidewalk. completed structure. It was built by the Union Bridge with the inevitable objections of those interested in and on the other side one of five and one-half feet Works. It is of steel throughout. Thecaissons were steamboats in T i ot l width of twenty-four and sunk in ec nd January nd of ply g on the river. Many predicted that width. h s giyes a t a D ember, 1887, a a February it would be impossible to construct it. The Missouri one-half feet. this year. The first piece of metal was put in position River, noted for its swift current, at this point at­ The floats . are anchored by a very perfect system, February 13, and on June 8 the last piece was in place. The river and one which, it is believed, will stand every condi­ et 325 feet tains about its highest velocity. carries The through spans are 400 fe . the deck span with it n and trees, tion the ·structure is likely to t long. length t ma y floatinglogs which alone would be exposed o. When it The entire of the bridge is 1,128 fee Iwd seem to make the maintenance of snch ­ in uild n the water was within two its g tons. The stone piers are 85 feet a structure im was process of b i g, wei ht is 1,489 possible. feet of high water mark, and the river swept dowp high and are 18 by 46 feet area at their bases. The river l g and at this point has two arms. Over one of many o s trees of great size. Numbers were car­ The pontoon bridge has proved so successful that it having by the current under boats wit t p them a permanent cribwork bridge passes, a ried the hou any bad has been proposed to form a com any for the construc­ of feet. it on is of ntoo the toW length 1.050 Where stops the p toon effects. For t4e spripg tl99<1/1 it proposed to greatly tic;m po n bridges across Missouri River, © 1888 SCIENTIFIC AMERICAN, INC. JCltutific �mtri.cau. ("NOVEMBER 10, 1888. considerations of cheapness and prac­ TO. LONG LIFE. Certainly, from FACTS AS ticability, they would seem to leave little to be desired. What tends to long life is a study with more profit The multiplication of bridges across the great rivers of as facts are used for data. The editor of a Boston the West is a movement in the direction of advanced paper, unread in theory, sent blanks ESTABLISHED 1845. through Massa· civilization. The sim ple and cheap pontoon bridges, chusetts to men and women of eighty years and more, by their number, may be made to do better work in inquiring as to habits, stat.e of eyes, teeth, hearing, facilit.ating intercourse than would be effected by a MUNN & CO., Editors and Proprietors. and the like, getting over 3,500 replies, and if in these slllaller number of more pretentiQus structures. For PUBLISHED WEEKLY AT there is nothing to refute the assertions of the theorists, some years their service may be all that will be desired, there is yet not anything to sustain them. aOll, as they prove inadequate, one by one they can be No. 361 BROADWAY, NEW YORK. They ate meat, save in a few cases, ad lib., and replaced by more permanent works. though none of them, if we take their own word for it, .. ,e,. O. D. MUNN. A. E. BEACH. have drunk freely of spirits, all, or nearly all, have Solidification oC PoW'dered Me tals. taken of them on occasion. These old people are from Professor Chandler Roberts Austen dealt with the 'rERMS POR 'rHE SCIEN'rIPIC AMEIUCAN. cities, towns, agricultural and maritime districts, in formation of solid metals by compressing strongly the une copy. one year. for the V. S. or Canada ........ ..... ....... ... .. ..S3 00 nearly all cases leading active lives, eating three meals copy, for V. or Canada . 1 :iO powders of the constituent metals. Since 1878, the One .lx mooths. the S. ..... ... .... .... .. a day, the dinner being, as is the custom in New Eng· One copy, one year, to any foreig-ncountry belonging to Postal Union, 4 00 labors of Professor Walthere Spring, of the University ltemitby postal or express money order. land, in the middle of the day, of meat and vegetable8, of Liege, have been mainly devoted to the study of A u8tralia. and New Zealand.-Those who desire to receive the and pie, and very hearty. Curiously enough, though the effect of compression on various bodies. Tbe par­ SCIENTIFJC AMERICAN, for a little over one year. may remit.£1in current the women are of medium height, Colonial bank notes. Address the men are mostly lic powder left to itself at the ordinary tall, above the average; ticles of a metal MUNN & CO., 3til Broadwuy. corner of Franklin Street. New York. and so greatly do blue and atmospheric pressure will not unite, but by augmenting gray eyes prevail that other shades 'rile Sclelltlfic Amerlcall SnpI'iemell' are notable excep­ the points of contact in a powder, the result may he is a distinct paper from the SCIENTIFIC AMItRICAN.THE SV PPLII:�lIl:N'l' tions. Baldness is rare, the hair being usually brown very different. Professor Austen's experiments were is issued weekly. Every number contains 16 octavo pages.uniform in size and thick, but the teeth are very poor or entirely gone. with SCIEN'rIFIC AMERICAN. 'l'erms of subscription for SUPPLEMENT, The made with the aid of a compression apparatus, in $6.00 report says : M.OOa year, for V. S. and Canada. a year to foreign countries belong­ which the metallic powder is placed under a short cyl- Inll( to the Postal Vnion. Sinll(le copies,lU cents. Sold by all newsdealers " These old people, men and women alike, are early inder of steel in a cavity in a steel block divided ver- throughcut tbe country. risers almost without exception, and fully nineteen out SCIENTIFIC AMERICAN and SUPPLEMENT tically, held together by a co ar.