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SCIENTIFIC NEWS. 



[May II, iS 



construction as might be necessary for medical purposes. 

 While such would be the functions of the College in 

 relation to the education of practitioners, steps would also 

 be taken to teach the public the immutability of the 

 natural laws on which sanitary science depends, and the 

 inevitable consequences which follow the violation of 

 those laws. If no more is done than the breaking down 

 of the generally prevailing ignorance and indifference 

 on this all-important subject, no mean thing will have 

 been accomplished. 



SCIENTIFIC TABLE TALK. 



By W. Mattieu Williams, F.R.A.S., F.C.S. 

 On page 394 of this magazine is an abstract of Adheniar's 

 bold speculation concerning the alternate arctic and ant- 

 arctic accumulation of an ice mountain 60 miles high from 

 the sea bottom, undermined by the water, and resting on a 

 huge pedestal. Besides the serious objections stated in the 

 article referred to, there is another that is fatal to this and 

 to all other assumptions of polar ice caps of great height 

 and steepness. I refer to the fact that ice is sufficiently 

 plastic or viscous to flow down any outlet that presents 

 itself when urged by the pressure of a great superin- 

 cumbent mass. As Forbes showed long ago, the glaciers 

 of the Alps are thus produced. They are the outflow of 

 the nev6 or great ice fields above. 



A grand example of this is presented by the Justedals- 

 brae in Norway, the largest mass of ice, i.e., the largest 

 neve in Europe. It is a tableland piled up with snow, 

 that has settled down into blue ice with an unbroken 

 area of about 500 square miles. The central portions of 

 this are somewhat higher than the boundaries, and, con- 

 sequently, the pressure of the ice upon itself produces a 

 creeping outflow in all directions, the mode of outflow 

 varying with the ground. Generally, the boundary of the 

 tableland has the usual form of long eroded grooves or 

 notches, i.e., ordinary steep valleys. All of these (so 

 numerous that they have not been counted) are wholly 

 or partiaUy filled with down-flowing glaciers, similar to 

 those of the Alps, some of them very fine. This is 

 especially the case with those that flow into the magni- 

 ficent valley which bears the general name of the Justedal. 

 But in some places the overflow takes a different 

 form, viz., that of a veritable cascade of ice pouring over 

 a precipice. This occurs when the table-land is bounded 

 by a perpendicular wall of rock, i.e., where the conditions 

 are the same as those producing a cascade of water where 

 the upland receives rain instead of snow. 



In the course of my solitary pedestrian wanderings 

 hereabouts in 1856, I came unexpectedly on a fine example 

 of this. After climbing over a great tract of glacier 

 debris, and glacier-planed rock, I reached the summit of 

 the Handspiken field, a region then unknown to English 

 tourists, and stood upon the shore of the head water of 

 the Justedal river, worthily named Styggevandet , the 

 hideous lake. The opposite shore was a gloomy preci- 

 pice of dark rock in deep shade, fringed at the top with 

 a blue crystal ridge through which the sun was shining. 

 This was a portion of the N.E. boundary of the great ice 

 field. Floating on the lake below were some small ice- 

 bergs, the origin of which was revealed by further obser- 

 vation. Some parts of the upper blue fringe of the black 

 precipice were perpendicular upward continuations of 

 the rock itself, walls of clear ice. At other parts there 



were great bending sheets, or overhanging cornices of 

 ice, extending for some distance downward over the face 

 of the dark rock, and with great icicles fringing the lower 

 part of the cornice. Here and there were crevices just 

 above the edge of the rock where the bending was the 

 sharpest. It was evident that these were overflowing 

 downpours from the great ice region above, and although 

 none came down while I was there, it was also evident 

 that the weight of the down-hanging masses must pre- 

 sently exceed the tenacity of the ice at the edge of the 

 rock, and then they must break off just there where the 

 cracks were threatening ; thus leaving an ice-wall at the 

 place of fracture, and supplying another little iceberg 

 to float on the lake. 



Such bending over and gradual breaking off would 

 follow any undermining of any great ice-wall, and pre- 

 vent any such catastrophe as Adhemar describes. His 

 sixty-mile heap of polar ice, or even the twenty-four- 

 mile heap of Croll would be impossible with a steep 

 slope. The summit pressure would bulge out the 

 boundaries, giving the whole ice-cap the oblate speroidal 

 shape of a batch-cake formed by a lump of dough left to 

 its own gravitating resources on the hot plate of an oven, 

 and this would go on subsiding and outspreading, to 

 form an ice sheet rather than an ice mountain. 



The plasticity of ice is well illustrated by an experi- 

 ment I devised some years ago. I had a strong iron 

 syringe, the piston of which was actuated by a screw. 

 Pieces of ice about half an inch across were placed in 

 the cylinder. On screwing down the piston the 

 ice was squirted into long sticks about one-twentieth of an 

 inch in diameter. A similar experiment has been made 

 by filling a bombshell with water and exposing it to a 

 freezing temperature. A crust of ice is first formed all 

 round the inner surface of the shell, then, as the expansion 

 due to the freezing of the inner water proceeds some of 

 this ice is wedged outwards and forms a stick of ice pro- 

 truding from the fuse hole. A similar experiment may 

 be made by using a strong phial. Unless the phial 

 breaks, a plug of ice will protrude from the neck. The 

 smaller the neck the more striking the experiment. A 

 champagne bottle may be used. 



Our vegetarian friends are very earnest in advocating 

 the use of whole-meal bread, and there is no doubt that 

 the arguments they use in its favour have considerable 

 force, but, as usually stated they involve a rather serious 

 error. Whole meal, properly so called, includes all that 

 is obtained by grinding wheat, i.e., the flour, the pollard, 

 and the bran. The bran is the outer husk or cuticle of 

 the wheat, which is so tough and so woody in its structure 

 (it consists, in fact, chiefly of cellulose or woody fibre) 

 that ordinary millstones do not grind it ; they merely 

 peel it off the grain in the form of scales of considerable 

 size. The following is Dr. Pavy's account of this husk, 

 or " tegumentary portion " of the wheat. It " constitutes 

 the greater bulk of the bran, and is of a perfectly indi- 

 gestible nature, and therefore useless as an article of 

 nutrition. Moreover, it acts, to some extent, as an 

 irritant to the alimentary canal , and thus, whilst of 

 service, retained with the flour, in cases where constipa- 

 tion exists, it should be avoided in irritable states of the 

 bowels, and also by those who work hard, for with these 

 it is likely to hurry the food too quickly through the 

 alimentary tract, and occasion waste by promoting its 

 escape without undergoing digestion and absorption." 

 ("A Treatise on Food and Dietetics," p. 211.) 



