Chemical Digest
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ABSTRACTS The Atmosphere: Origin and Composition. W. J. HUMPHREY~. Sci. Mo., 24, 2 1 P 9 (March, 1927).-It is believed that all matter consists of some combination or a.iseml,lilgc ui two things ns yc,t unrrsui\~crl-the electron ard thc proton These exist in equal quantities in all matter. Hence, whercvcr matter occurs i n great quantities. ns in a star ur a d a n r t . one m a v rrtrcct to find e v m ims.;il~lrcom1,m;ttiun of elect& and proton, i. e., all the c h e m i d eiements and such'of their compoundsas the existing tem&atures may favor E v w y hcaverlly ohjtxt, therrfort, h l r t h C ,makings of an atmocphrre Thc atntmpherr of thr mrth forrued herausr of a dttfcrence in the cffrct oi cravitv and the wrlurnrl of steam. cnrhon diuxidr. nitroucn. hvdroeen. and other ~ a &let-loose t h r o u ~ heruptions in the earth's crust It 6 p ~ o d a b l y ~ b e ~ cause of the nctivity oi uxywn at hixl, rempcmturreviously which these pressures call be measured accurately. Very few measurements have been made of the vapor pressures 01 the alkali metals and thesc usually a t high temperatures. Here data from experimental work have been comparcd with pressures extrapolated from various formulas. No single formula represents the variation of pressure with tcmperature for any given metal, but lrom a comparison of all thc results it is possible to get an approximate valuation of the pressures a t various temperatures. E. S . R. Peasantry or Power. MACYCAMPBBLL. 1. Nail. Edac. Assoc., 16, 73-6 (March, 10Zi).-Hcrr are statcd two aspects of the agricultural problem, a problem more far-reaching than that of slavery, for it is a problem of economic freedom for thirty million people. First, those who till the soil are gradually losing ownership of the land. The proportion of landless farmers is gradually increasing. As a conscqoence of this, the more capahlc young people will not stay on the farm and the land loses its best brains, only the "small potatoes are left." The percentage of feeblemindrd in rural districts is higher. Brains from the farmarenot running big businessorganizations wherc money is to he made. The remedy, says Mr. Campbell, isintelligent organization-cobpcration on an immense scale, with the best,brains al the farm leading the advance. This is to be done by the enlightenment of the young on the advantages of tcam work and training in group action. In the end all go up and dawn with E. S. R. the farmer. In Self Defense. BARNETRUDMAN. Educ., 47, 4GR71 (Apr., 1927).-A clever and convincing protest against the undercurrent of popular opinion which occasionally finds expression in such a phrase as, "Let us have an expert. not a schoolteacher." The article indicates the line of the teaching profession, its adventure, its ultimate usefulness and possibility of spiritual wealth, and its demand for personality E. S. R. and courage in the face of public opinion. Thennit and Icebergs. H. T. BARNES. I. Frank. Inst., 203, 6 1 1 3 4 (May, Ig27).-Researches of thirty years ago showed B. that the equilibrium between the solid and liquid phases of water is most delicately balanced, and that when there is a temperature changc of a minute fraction of a degree, one phase passes over into the other. The true freezing-point of water has to bc defined as that of an intimate minture 01 ice and water neither gaining nor losing heat. Practical application of thesmall temperature effcct has heen made use of to prevent the accumulation of ice, this requiring vastly less actual heat than getting rid of ice after it has been formed. Nature points the way to the powerful influence of the sun as a fighting tool. In selecting a radiant beam for ice control, the selective absorption of water for heat rays must be cardully considered. In 1021 R. made studies with icebergs off Newloundland; later with ice packs in t h e s t . LawrcnceRiver. %. material known to the trade
a.
for twenty-five years as thermit, a n exothermic mixture of aluminum metal and iron oxide, was uscd in all the experiments. A temperature varying from 2500°C. to 3500'C. is produced in a few seconds. The actual number of heat units per pound of material is anlv 1500. much less thawfor coal. As soon as the molten iron comes in direct contact with the ice or water a second rcactim takes place whwh decompose. the wotcr into oayycn nnd hydropcn. There is well n rapid vvulutiun uf yns t h n ~a slow crplorion tak:s placc. The thermit furniches h v ~ t2nd runlosirm. The irnnortant fact is the outout of cneruv in thc " m e tratinp- heat rays which overcomes'the enceedindv small ' t e m ~ e r a t u ~ ~ e f f e i;c t sthe watcr. An irel;crr: give%the Iw5t eranlplr of tlw rif&t of strnin ~IIIIUCPIIh y the t h ~ r m i t , ac it is hy iar rhe lardect mats of solid hard icr thnt could he v\prrirr.mtrd wth. livrry unit nut into m ice nack 3C1, 3s a ivoint of m!e~tim which ~ I I T P O\W R ~ ~ a ~ " L . T C B ~ W ilnd me&r area until t
