May 15, 1903.] 



SCIENCE. 



791 



Tlie paper will be published in an early num- 

 ber of Popular Astronomy. 



Dr. A. L. Day, of the Geological Survey, 

 discussed ' The Melting Point of a Glass,' bas- 

 ing his remarks on a study of borax glass, 

 which has a melting point in the neighborhood 

 of 730° as determined in ordinary ways. If 

 ordinary solid bodies have heat communicated 

 to them the temperature gradually rises till 

 melting- begins, when it remains stationary 

 till melting is complete; and a corresponding 

 phenomenon takes place on cooling from liquid 

 to solid. So the curve of temperature as a 

 function of the time shows a portion^ parallel 

 to the axis of the time. The borax glass, if 

 in the crystalline state, shows a similar 

 straight portion, or at least a departure from 

 the smooth curve; but if in the vitreous stage 

 the curve may be perfectly smooth, and the 

 material pass from liquid to solid without 

 showing any phenomena by which to fix a 

 melting point, as ordinarily defined. 



The 568th meeting was held April 25, 1903, 

 in the rooms of the National Bureau of Stand- 

 ards through the courtesy of Director S. W. 

 Stratton. No formal papers were presented, 

 but the laboratories and shops were opened, 

 and many new instruments were exhibited and 

 explained informally. The evening was one 

 of great interest to all visitors. 



Charles K. Wead, 



Secretary. 



BIOLOGICAL SOCIETY OF WASHINGTOJS^ 



The 371st meeting of the society was held 

 on Saturday, April 18. 



W. J. Spillman spoke on ' Agrostological 

 Problems in the United States,' using a num- 

 ber of lantern slides by way of illustration. 

 These slides were prepared from the recent 

 census reports, and showed the distribution 

 of each of the important hay and forage crops 

 over the country. He brought out the rather 

 remarkable fact that by far the larger part 

 of the hay and forage produced in this coun- 

 try is produced on the glacial drift, also that 

 one fourth of the total hay and forage is pro- 

 duced from wild grasses, and that of the wild 

 grasses that are thus utilized no one of them 

 has as yet been brought into cultivation. The 



principal reason for this lies in the poor seed 

 habits of these grasses, a fact which renders 

 their use impracticable. He also gave some 

 illustrations of the relation between certain 

 crops and certain geological formations. It 

 was shown that, in the state of Kentucky, 

 Kentucky blue grass {Poa pratensis) is eon- 

 fined to a circular area in the northern part 

 of the state, in which the dolomitic limestones 

 of the Silurian outcrop. In a similar man- 

 ner Johnson grass in the southern states is 

 more or less closely confined to the soils of 

 the Cretaceous. He pointed out the impor- 

 tance of increasing the areas of hay and for- 

 age crops, particularly in the cotton belt, 

 where the system of farming has depleted the 

 soil of humus to such an extent as greatly 

 to interfere with its productivity. He stated 

 that another very important problem was to 

 secure suitable crops for the arid and semi- 

 arid regions that could be grown without irri- 

 gation, and that some progress has been made 

 in this direction. 



A paper by Basil Dutcher, captain U. S. 

 Army (Medical Corps), on the 'Mammals of 

 Mount Katahdin,' was read by Vernon Bailey. 

 The topography of the region was carefully 

 described, and this was followed by a fully 

 annotated list of the marmnals. Of the 

 larger species the moose was fairly common, 

 the Virginia deer abundant, while the otter 

 and lynx were still found in the vicinity. 

 Small carnivores, the fishes, mink and weasel 

 Were said to be common, but Mr. Dutcher 

 was able to trap but few small rodents, the 

 only really abundant rodent being the musk- 

 rat. The fauna was that of the Canadian 

 region, and not that of the Hudsonian. 



In his paper, entitled ' Notes on the Dis- 

 semination of Sedum douglasii by Proliferous 

 Shoots,' Mr. V. K. Chesnut drew attention 

 to a comparatively undescribed natural meth- 

 od of plant reproduction. Sedum douglasii, 

 a plant growing at an altitude of about 7,000 

 feet in Montana, forms axillary branches 

 about a half inch long, which, late in the 

 summer, become detached from the dried 

 stem after the plant has flowered, and which 

 are capable of reproducing the plant vege- 

 tatively. The light, spear-shaped branches 



