454 



♦ KNOWLEDGE ♦ 



[Marcu 24, 1882. 



CHALCEDONY CONTAINlNtJ LIQUID WITH A 

 M0VA15LE BUBBLE. 



Ilv TIIK Ukv, UeMIV H. UlGUIN.--. 



Two ipocimuiiB wore bruiif^lit from Moiilo Video by Mr. riiiliji 

 Itntliboiiiv Till" liir«iT )iiceo contaliiH not loss than nn niincu '\ 

 uf lii|tii(l, with u hirgu huhlilc— the Hninlh-r sncins to huvo iiiiiro 

 litliiid in iiri>|><ii'tioii. A third apeciniin is broken, showing thownlls 

 of the cliiiniber to be, in the thinnest part, not more than y^ "f "" 

 inch in tliiokness. The mineral seems to have been recently dis- 

 eovered, no mention of it beinff mndo in Dana's text-book, 1880. 

 K. \V. Kudlor, Professor of llineralojfy in the Hoyal School of Mines, 

 informs me that he has not scon any published description of 

 Chalcedony cnclosinf^ water with n movable bubble. I am not a 

 niiucrulogist, and nmke the following eonjectuies with much dilli- 

 deucc. In some cavity deep in the earth, and probably umler prcat 

 pressure, occurred a hollow containing a small quantity of watei-, 

 above the boiling point, but kept liquid by pressure, and Buper- 

 eaturated with silica. On any diminution of the temperature, 

 which might occur extremely slowly, the fall of one degree 

 occui)ying perhaps long ages, crystallisation would set in on all the 

 sides of the hollow holding the liquid, and at the same time would 

 bo formed on the sulfate of the water, a crystalline pellicle, from 

 which crystals woulil shoot downwards and inwards. Thus would 

 be formed a cavity enclosed on all sides and filled with liquid. 

 Layers of opuliscd (|uart7., chalcedony, might now be deposited 

 externally upon the roots of the crystals, forming a cell with walls 

 impervious to water or gas. Further diminution of temperature 

 would enable minute quantities of gas contained in the water to 

 assume a gaseous form and unite in a bubble. In the broken 

 specimen, the walls distinctly show the radial disposition of the 

 crystals forming the lining, and the stalagmitic character of the 

 outer rind in which the chalcedony is deposited in layers like the 

 laminoo of an onyx or an agate. In the large specimen, the outer 

 surface is very interesting. It is covered with low tubercles 

 arranged in circles J in. in diameter, each circle having within it 

 several similar concentric circles. The cavity is not strong enough 

 to withstand any considerable bursting pressure from within. It is 

 possible, however, that the shrinkage of the contents of the cavity 

 from cold may have maintained the equilibrium between outside and 

 inside pressures. Although the tank-forming chalcedonies do not 

 appear to have been described, quartz crystals with minute drops 

 of movable bubbles enclosed have long been common in all col- 

 lections of minerals. 



John W. Judd, F.R.S., in his admirable work on volcanoes, gives 

 the best, almost the only description 1 have seen of them. The 

 liquid may be water, a hydrocarbon, or even carbon dioxide. That 

 it may be the last has been proved by spectrum analysis, and by the 

 test that when the crystal is heated to 86" or 90° Fahrenheit, the 

 bubble disappears ; that temperature being for carbonic dioxide, the 

 critical point above which no pressure can keep it in a state of 

 liquidity. Still more remarkable is Mr. Judd's account of micro- 

 scopic cavities containing liquid in which the bubble is in constant 

 motion, pursuing a sjiiral track from end to end of the cavity. For 

 the only attempt at explanation of this motion yet given, Mr. Judd's 

 work may be consulted, and no one will regret having read the 

 book from the first to the last page. All the cavities of which 

 Mr. Judd speaks are very minute, and it is evident that the tank- 

 forming chalcedonies are constructed in some manner to which the 

 quartz crystals containing drops can afford no suificienl clue, though 

 as in my own case, Mr. Judd's beautiful researches may lead to 

 more or less reasonable guesses. Through the kindness of Mr. 

 Rathbone, the smaller specimen and the equally interesting broken 

 one have been placed in the Liverpool museum . 



MODERN DRESS. 



Ij^CCENTKlClTIES of costume have iu all ages formed a pronii- 

 -J nent subject on which satirists have expended the magazine of 

 their wit ; and in the present day no inconsiderable attention is 

 given to it by those who make it a business to caricature the follies 

 of their fellow beings. It is, however, an all but recent develop- 

 ment that is being witnessed now in connection with the efforts 

 made by the medical profession to awaken the public to a sense of 

 the self-inflicted evils suffered from absurd compliance with the 

 demands of " fashion." Nor can we feel anything but sincere satis- 

 faction that this question has so far become a " burning ** One ; and 

 that men of the highest eminence deem it part of their duty to 

 society to issue warnings against the miserable consequences of 

 sacrifices offered to the shrine of appearance. The jihysical erils of 

 ina])proprlate dress are so manifest to the physiologist, the consti- 

 tutional damage they entail so apparent to the physician, the 



misorioR they create ao ovidout to the social economist, that it is 

 rnthor a matter of wonder they have so long been [icrmittcd to 

 continue unchecked and unroformod. Now and again, indeed, 

 indiviiluuls in the |>aHt have raised a warning voice against indul- 

 gonco in the fashionable caprices of their time ; but never before 

 has a detormini'd attempt to improve jiublic ta<ite and educate 

 )>ublie ignorance in the matter of dress 1>eon made that characterises 

 the action of the National Health Society in this respect. Re- 

 cently, however, Mr. Fre<lerick Treves, F.U.CS., of the Ixindon 

 Hospital, delivered a lecture before a crowded audience in the 

 Kensington Hall, on Ijchnlf of the National Health Society, the 

 subject selected being, " The Dress of the Period." It is gratifying 

 to hear that nnusual interest was excited by the preliminary 

 announcements; wc shall perhaps be indulging in unlicensed hopes, 

 however, if we |>ennit this result to create in our minds a belief to 

 the effect that the public arc at last growing alive to the harmful- 

 ness of following the dictates of fashion mth the unreasoning sub- 

 mission exhibited iu the adoption of its most outrageous demands. 

 It is true the auilicnca which greeted Mr. Trcves's domonslrations 

 of modern fashionable follies with applause, indicative of its 

 approval of his denunciations, was chiefly made up of ladies whose 

 claim to be regarded more or less as victims to the Moloch under 

 censure was indisputable ; but notwithstanding, it would be the 

 refinement of rashness to expect from them an immediate renun- 

 ciation of tight waists, cramped feet, and swathed limbs. The hold 

 of these on the lives of those who form " society " is too secure and 

 too steadfastly maintained to permit its being easily removed. We 

 can trust for this happy result to nothing but a general and an 

 intelhgent apprehension of the mischief attendant on continuance of 

 the evils which carry such disasters in their train. 



The ill-conse(|uences set up by improjicr dress are most faniiliar 

 to medical men ; and medical men necessarily, therefore, are those 

 most competent to advwcate reform in customs* to the injarions 

 effects of which they are daily witnesses. In the particular folly of 

 tight lacing, for instance, there is probably no practitioner who is 

 not constantly called on to remedy the evils it produces. In young 

 girls, who, least of all, are calculated to support the strain to which 

 their internal organs are submitted imder the cruel pressure of the 

 corset, we have often to deal with piteous examples of the sacrifices 

 required in order to ensure a small waist. Nor is it that they suffer 

 only while young. During their whole after-life, symptoms referable 

 to visceral displacement and disorganisation are of frequent occur- 

 rence ; no woman, probably, who has at any time conformed to this 

 fashion of abdomen-strajiping being free from some form of gastric 

 or liver trouble. To what extent, moreover, the craze for " an 

 elegant figure " may carry its victim is scarcely credible, except for 

 occasional proofs afforded at inquests and post-mortem examinations. 

 While it is not unusual to find the liver deeply indented by pressure 

 of the adjacent ribs and displaced deep into the pelvis, it has more 

 than once been found that long-continued constriction of the body 

 has resulted in hour-glass deformity of the stomach. Nor need we 

 long hesitate to decide on the influence this vicious form of fashion- 

 able sacrifice e.verts on the duration of female life, when we reflect 

 on the prevalence among the middle and upper clas.<es of the very 

 diseases which vfould be induced by persistence in such habits. 

 Gastric ulcer is at least three times as frequent in women as it is in 

 men. Syncope is a common form of weakness exhibited by young 

 women who subject their viscera to the vice-like compression of a 

 corset ; and the intestinal troubles set up by interference with the 

 functions of the liver, together with the distributed pressure on the 

 intestines themselves, are among the most productive sources of 

 feminine illness. Indeed, the subject of tight lacing might with 

 advantage be taken as the sole topic for a considerable number of 

 lectures ; and the more tellingly the evils it ensures are put before 

 the public, the more convincingly they can be taught to perceive 

 the fatal injury the practice is doing to the race, the more speedily 

 and surely will it cease to bo commonly indulged in. We wonld 

 urge thispoint — that of the injury suffered through it by the whole 

 race — witli especial force. By as much as any woman undermines 

 her own health — it matters not in what manner the mischief is done 

 — to such an extent is she also injuring the physique that will be 

 inherited by her children. Perhaps, by exciting the maternal 

 instinct, more benefit will be derived than by any other means at 

 present devised. At any rate, the proposal deserves consideration. 

 Apart from tight lacing, there are other evils associated with 

 modern clothing that deserve equal attention. Space forbids more 

 than a mention of them now, but we may instance the inadequacy 

 of modern dress to secure either of the two imjwrtunt desiderata — 

 appropriate protection and equable temperature. As Mr. Treves 

 pointed out to his audience, a fashionably-dressed woman of to-tlay 

 is all but nude about the chest and back, at most but a thin, single 

 or double layer of material protecting these delicate and suscep- 

 tible regions, while a hnge mass of useless clothing is swathed about 

 the hips and legs, and trails in abundant prodigality to clothe the 



