October 4, 1901.] 



SCIENCE. 



537 



ably. The older methods of obtaining sulfur 

 from its ore by setting fire, to it in covered 

 heaps or in kilns, -where the sulfur itself served 

 as fuel, have been discarded both on account 

 of the waste and because of the intolerable 

 nuisance to which the fumes of the burning 

 sulfur gave rise. Coal is in general used as 

 fuel, although very expensive. Extraction of 

 the sulfur with carbon bisulfid or with a con- 

 centrated solution of calcium chlorid is in 

 many cases used, but the only method in which 

 no noxious fumes are generated is the extrac- 

 tion with steam under pressure. The extent 

 of the industry is rapidly increasing and Sicily 

 will long continue to supply the major part of 

 the world's production. 



The use of sulfur as a fungicide is rapidly 

 increasing in the continental vineyards, and for 

 this purpose it is necessary that the sulfur shall 

 be in the most finely divided condition possible. 

 Flowers of sulfur were at first used, and then 

 ground and sifted refined sulfur, but a large 

 portion of even this was wasted on account of 

 the size of the particles. ' Blown ' sulfur {zolfo 

 ventilato) has lately come into extensive use. 

 The finely ground sulfur is carried by an end- 

 less chain into a strong current of air, or for 

 the purpose of avoiding explosions, of gases as 

 free as possible from oxygen. The sulfur dust 

 is carried into large settling chambers where 

 all the larger particles are separated by their 

 more rapid deposition. The sulfur dust thus 

 obtained is pale yellow, resembling precipitated 

 sulfur, and is found to be very satisfactory for 

 fungicidal purposes. 



J. L. H. 



OUBBENT NOTES ON PHYSIOQBAPHY. 

 PHYSIOGRAPHIC GEOLOGY. 



^ ^ The increasing recognition of physiography 

 as related to geology is illustrated in Brigham's 

 excellent contribution to the Twentieth Century 

 series ('A Text-book of Geology,' New York, 

 Appleton, 1901, pp. 477, many illustrations). 

 A chapter of forty pages in the middle of the 

 book, devoted to 'Physiographic Structures,' 

 presents a compact epitome of the subject, in- 

 cluding a consideration of forms as the result 

 of processes, with a brief exposition of the cycle 

 of erosion and development of drainage. On 



the other hand, physiographic discipline is not 

 likely to be gained in forty pages, as appears 

 from the scanty treatment of so important a 

 matter as the adjustment of drainage (284-), the 

 explanation of which, as here given, can hardly 

 be appreciated by those who do not already 

 understand it. It may be questioned whether 

 the categorical method of separating folded 

 structures (223-) from the origin and form of 

 folded mountains (256-) is as effective, a method 

 of presenting the real earth to beginners as 

 would be found in a closer connection of these 

 naturally associated facts. The same may be 

 said of volcanic processes (135-) and volcanic 

 topogi-aphy (262-), and of glacial processes 

 (91-) and glacial topography (266-). There 

 may be abundant px'ecedent for the categorical 

 arrangement, and some justification for it in 

 teaching ; but a more natural method would 

 bring process and form closer together. 



GLACIAL LAKES IN MINNESOTA. 



WiNCHELL summarizes the history of twenty- 

 six ' Glacial Lakes in Minnesota ' {Bull. Geol. 

 Soc. Amer., XII., 1901, 109-128, map), whose 

 geographical consequences are seen in gravel 

 and silt deposits, shore lines and especially in 

 outlet channels. The lake waters were held 

 up by the retreating ice lobes of the Superior 

 and Eed river troughs. The most famous of 

 them is Lake Agassiz, so fully described by 

 Upham (Monogr. XXV., U. S. Geol. Surv.). 

 The others were much smaller, and their out- 

 lines are at present but imperfectly traced. 

 The outlet channels are of moderate depths, 

 but are usually well defined by banks carved in 

 till ; the channel floors are sometimes without 

 streams, sometimes occupied by small streams, 

 sometimes partly covered with shallow ponds 

 or sloughs. The fuller details of this com- 

 plicated lake system will afford material for 

 local studies for years to come. 



ESKER LAKES IN INDIANA. 



Dryer, who has already described the ' mo- 

 rainic lakes of Indiana' ('Studies in Indiana 

 Geography,' Terre Haute, 1897, 53-60), now 

 gives an account of ' certain peculiar eskers and 

 esker lakes of northeastern Indiana,' (Joum. 

 Geol., IX., 1901, 123-129, 2 maps). The region 

 concerned is traversed by a series of massive 



