May 22, 1885. 



SCIENCE. 



427 



Holland possesses the great advantage of holding 

 the mouths of the Rhine, the Maas, and the Scheldt. 

 Her means of river communication with Germany, 

 France, and Belgium, are unbounded ; and the posses- 

 sion of a length of 930 miles of canals and 340 miles 

 of rivers enables her, apart from her railways, to carry 

 on her large trade with greater facility of transport 

 than, perhaps, any other European country. 



Belgium shares with her northern neighbor the 

 advantages of an elaborate system of waterways. By 

 far the most important river is the Scheldt. Thanks 

 to its unique position at the head of a tidal estuary, 

 to the abolition of the Scheldt dues, and to the fore- 

 sight and liberality of the Belgian government, which 

 has spent $20,000,000 on dock and river works since 

 1877, Antwerp has now become in many respects the 

 foremost port of the continent. Besides her 700 

 miles of navigable rivers, Belgium possesses about 

 540 miles of canals, by means of which communica- 

 tion exists between all the large towns and chief sea- 

 ports of the kingdom. 



France has built up, and is constantly extending, 

 an elaborate system of canals and canalized rivers. 

 Of the latter, the Seine is the most important in re- 

 gard to the artificial works undertaken for its im- 

 provement, and for the tonnage of the traffic, which 

 was in 1872 more than one-eighth of the whole water- 

 borne traffic of France. The Loire, the Garonne, 

 and the Ehone have all been largely benefited by the 

 art of the engineer. The canal system of France is 

 historic; one of the earliest of these artificial cuts 

 being the celebrated canal of Languedoc, 171 miles 

 long, built in 1667-81, and now forming part of the 

 Canal du Midi. From its summit-level 600 feet 

 above the sea, it communicates with the Garonne, 

 and therefore with the Atlantic, by twenty-six locks, 

 while its southern slope descends by seventy-three 

 locks to the Mediterranean. Up to 1878, on 7,069 

 miles of waterways, France had spent upwards of 

 §215,000,000. Nevertheless, it is intended still fur- 

 ther to extend this means of communication at an 

 estimated further cost of $200,000,000. 



Spain and Portugal possess, partly in common, eight 

 principal rivers, of which five — the Minho, Douro, 

 Tagus, Guadiana, and Guadalquivir — drain the wes- 

 tern valleys, and flow into the Atlantic; while the 

 other three — the Ebro, Incar, and Segura — discharge 

 into the Mediterranean. As a rule, these rivers are 

 only navigable for a limited portion of their course, 

 and are chiefly remarkable for extremes of flood- 

 discharge ; a velocity of sixteen knots an hour having 

 been noted in the Douro under certain conditions of 

 tide. The canals of the Iberian peninsula are unimpor- 

 tant. Spain possessed a length of 130 miles in 1875. 



Italy is not rich in waterways except in the valley 

 of the Po, the navigable portion of her rivers only 

 attaining an aggregate length of 1,100 miles. Al- 

 though the total length of navigable canals in Italy 

 is only 435 miles, the Italians were the first people of 

 modern Europe that attempted to plan and execute 

 such artificial waterways. As a rule, however, they 

 have been principally undertaken for the purposes of 

 irrigation. 



Austria-Hungary possesses in the Danube the 

 largest river in Europe as regards the volume of 

 discharge, although it is inferior to the Volga in the 

 length of its course and the area of its basin. This 

 great stream first becomes navigable for flat-bottomed 

 boats at Ulm, 130 miles from its source. In its total 

 length of 1,750 miles, it is fed by at least 300 tribu- 

 taries, many of them large rivers. Although the 

 Danube between Vienna and Old Moldova had been 

 regulated in numerous places and at great cost, there 

 had been but little appreciable improvement effected 

 in its general navigable depth. On this account, 

 projects having in view the permanent acquisition of 

 a sufficiently wide channel, of from six to eight feet 

 deep at every point between Passau and Basias, 

 have lately been prepared, which involve an outlay 

 of $10,000,000 to effect the desired improvements. 

 Traffic on the upper and lower Danube is mostly 

 carried in barges, of which the greater number gauge 

 250 tons. The effect of the improvements at the 

 Sulina mouth has been to increase the trade from 

 680,000 tons gross in 1859, to 1,530,000 gross tons in 

 1883, and to lower the charges on shipping from an 

 average of five dollars per ton for lighterage, to half 

 a dollar per register ton at the present time for com- 

 mission dues. As a commentary on the hostile crit- 

 icism evoked when the scheme was initiated, the 

 lecturer drew attention to two facts; namely, that 

 the works so unsparingly criticised in 1857 had 

 already effected a saving of $100,000,000, and that 

 experience had abundantly proved that the predic- 

 tions of a rapid silting-up to seaward of the Sulina 

 piers had been completely erroneous. 



THE GEOLOGY OF WISCONSIN. 



The nearly simultaneous appearance of the 

 two final volumes of the ' Geology of Wisconsin ' 

 some months since, marked the close of one 

 of the most rapid of the state geological sur- 

 veys, and, for the time and mone} T expended, 

 one of the most thorough and complete. The 

 work has been done in less detail than in some 

 other states, whose surveys have run through 

 much longer periods of time, and have con- 

 sequently necessitated much greater financial 

 outlays. The results are embodied in four 

 large octavo volumes, containing something 

 more than three thousand pages. The text is 

 well illustrated ; and the judicious use of 

 cuts, which express much more than the best 

 verbal descriptions occup} T ing the same space, 

 has contributed to the embodiment of a large 

 amount of material in relatively small compass. 

 In the same line may be noted the predomi- 

 nance of observational results over theoretical 

 deductions, and the absence of irrelevant dis- 

 cussions which have sometimes served to swell 



Geology of Wisconsin. Professor T. C. Chambekxix, chier 

 geologist. 4 vols. Madison, Wis., 1S77-83. 3,147 p., 1-40 pi. 8° 



