i6 



KNOWLEDGE & SCIENTIFIC NEWS. 



[January, 1907. 



the earliest investigations iiiti> thr chemistry of the plant 

 was that made in 1858, by K. l.iUcl, who found that it con- 

 tained a tannin, giving a green coloration with iron salts. 

 Me attributed the poisonous action of the juice to the 

 presence of an alkaloid. Soon afterwards, Porcher dis- 

 covered that the exhalations given olT at night by the leaves 

 contained hydorcarbons, whicli would burn when ignited. 

 Then, in 1805, Dr. iMaisch found that the eni.mations had 

 an acid reaction, and that tht' leaves contained ammonia 

 but no alkaloid, lie isolated a volatile substance, which 

 combined with alkalies to form salts, and to this substance, 

 which he termed tuxicoilciidiif aciil, he attributed the 

 poisonous action of both the juice and the exhalations, for 

 whether in solution or in the form of vapour it produced 

 the same elTects upon the skin. This was confirmed in 

 1883 bv Mr. Pettigrew, who found that the acid resembled 

 formic acid in many of its properties. Messrs. Acree and 

 .Svme have now separated from the juice a poisonous wax- 

 like substance, which does not volatilize when heated with 

 alcohol vapour. They have also proved that all cases of 

 poisoning can be cined by the use of a solution of potassium 

 permanganate. 



Spontaneous Igrnition of Carbon Bi- 

 sulphide. 



Carbon bisulphide, a mobile, highly refractive liquid, 

 prepared bv passing sulphur vapour over hot carbon, is ex- 

 trenu'lv valuable as a solvent for fats, for killing weevils 

 in grain, and for many other purposes, but serious draw- 

 backs attend its use. The ordinary commercial product has 

 a particularly ofTensive smell, whicli is commonly attributed 

 to the presence of traces of impurities. Then the vapour 

 is very poisonous, and workmen who handle the liquid in 

 badlv ventilated factories are liable to suffer from de- 

 pression, coma, and loss of memory. The greatest risk, 

 however, is due to its being highly inflammable, igniting 

 at quite a low temperature, and burning with a blue flame 

 to form carbon dioxide and sulphur dioxide. So great is 

 the innammability of carbon bisulphide, that numerous in- 

 stances have been recorded where it has taken fire spon- 

 taneously. In a recent case described by M. Pape, the 

 chemical became ignited when being poured through a 

 metal funnel into a glass carboy, in the open air, and far 

 away from any source of flame. The day was very hot and 

 dry, and the immediate cause appears to have been an 

 electric discharge caused by the friction of the liquid falling 

 upon the iron funnel, which was isolated by the glass of 

 the carboy. Other cases of spontaneous ignition have taken 

 place while the bisulphide was being poured into iron drums. 

 An electric discharge has also been looked upon as the chief 

 cause of these accidents, though it has been suggested that 

 the heat produced by oxidation of iron sulphide may have 

 had a share in the process. The remedy proposed is to 

 expel the air from the drums by means of an inert gas, such 

 as carbon dioxide, before introducing the carbon bisulphide. 



GEOLOGICAL. 



By Edward A. Martin, F.G.S. 



Phosphorescence in Calcite. 



In the American Journal of Science, Mr. W. P. Headden 

 has been discussing the phosphorescence of certain calcites 

 from Fort Collins, Colo., and Joplin, Mo. They possess 

 the property of becoming phosphorescent on being insolated, 

 and retain this property, in some cases, for a period of 

 thirteen hours. Ordinary calcite under like conditions 

 phosphoresces for one-third of a second, and aragonite for 

 twenty seconds. Many other minerals become phos- 

 phorescent on being insolated, but the duration of this 

 phosphorescence is very brief. 



The Missouri specimens, which show a stronger phos- 

 phorescence than those from Colorado, occur in two forms, 

 both in well-defined crystals. One is the well-known dogl 

 tooth spar, only slightly modified by a rhombohedron ; the 

 other is a combination of two scalenohedrons. 



The length of the period of phosphorescence was as much 

 as thirteen hours, which was established by continuous ob- 

 servation. The duration, no doubt, actually exceeded this 



lime, hut it w.is distinctly visible, in some specimens, for the 

 time given. 



Mr. lleadden concludes by rem.arking th.il "the limit of 

 mv ])resent progress is the establishment of a probability 

 that these calcites owe their properly of becoming phos- 

 phorescent on insolation to the presence of some member of 

 the yttriimi group, which is represented liy 1 ^ |)arts in e.ach 

 100,000 parts of the calcite." 



A Deep Borinfr at Lincoln. 



.\ conmiimicalion was re, id ,it the meeting of the deulogi- 

 cal Society on December i,(, by Prof. iviKvard Hull, on 

 " The (ieological Conditions which h.ave contributed to the 

 Success of the Artesian Boring for Water at Lincoln." 



The boring has its source of supply in strata which rise 

 to the west, but to the east dip down towards the North Sea. 

 There exists no information as to whether the eastern border 

 of the water-bearing formation thins out against a con- 

 cealed ridge of Pahco/oic rocks. The water-yielding 

 stratum is reddish soft, porous sand-rock, reached at a 

 depth of 1,561 feet and penetrated to a depth of 474 feet. 

 ,'\bout one million gallons of water rise to the surface daily. 

 The sand-rock belongs to the New Red .Sandstone, which 

 crops out from York to Nottingham with a breadth of about 

 eight miles. The hydraulic pressure at the bottom of the 

 boring is that due to about 2,035 feet, and the friction of 

 the water in percolating the rock accounts for the fact that 

 the writer can be [)uniped down during the day but rises 

 again in the night. The formations penetrated are the 

 following : — Alluvium and Lower Lias 641 feet, Rha^tic Beds 

 52 feet. Red Marl and I^ower Keuper .Sandstone 868 feet, 

 Bunter Sandstone 454 feet. The quantity of water drawn 

 from the New Red .Sandstone, at and below the outcrop 

 defined, amounts to not less than 20 million gallons daily, 

 and the total available quantity of water percolating into the 

 .Sandstone amounts to about 300 millions. 



Raised Beaches on the Chilian Coast. 



Mr. O. IL Evans' paper on " Tlie Raised Beaches of 

 Taltal (Northern Chile) " proved extremely interesting. The 

 town of Taltal is situated partly on the dry bed of a broad 

 river and partly on a gently-inclined plain that fringes the 

 bays of the coastal ranges far to the northward, and runs up 

 the valleys to a considerable altitude and distance from the 

 coast. The formation is impregnated with salt, and there 

 protrude through it curiously-weathered remnants of former 

 stacks and islets. The plain rises in terraces, the highest 

 of which are somewhat obscure, and sometimes portions of 

 these higher terraces are preserved in the stacks and islets. 

 A second coastal shelf also occurs, marked by a line of 

 shallow caverns. The beds of shells in the gravel, contain- 

 ing occasionally whale-bones, give satisfactory evidence of 

 the marine origin of the terraces. Some of these shells are 

 replaced by crystallised brine, and calcium sulphate occurs 

 in some sections. Profound ravines (quebradas) occur in 

 the massive rocks bordering the plain, although the climate 

 is now so dry that rain-erosion is practically non-existent. 

 Mr. Evans exhibited specimens in illustration of his paper, 

 but he had, unfortunately, lost almost the whole of his 

 collection, as well as his notes, in the earthquake at Val- 

 paraiso, whilst such as the earthquake spared had since 

 either been burnt or blown up by dynamite. 



ORNITHOLOGICAL. 



By W. P. Pycraft, A.L.S., F.Z.S., M.B.O.U., &c. 



The Range of the Arctic Tern. 



The recent Scottish National Antarctic Expedition was em- 

 phatically successful, and especially so, perhaps, with regard 

 to the biological work achieved by its officers. Much has 

 already been published on this head, and Mr. Eagle Clarke 

 added thereto at the meeting of the British Ornithologists' 

 Club held on November 21. At this gathering he exhibited 

 specimens of the Arctic Tern, which had been taken in the 

 Weddell Sea and off the Antarctic Continent, where great 

 numbers were observed as far south as 74°. All were 

 typical Arctic Terns {Sterna macrura), and thus this bird has 

 proved to have a greater latitudinal range than that of any 



