354 



NATURE 



[September i6, 1909 



It will add to the general estimation of the common 

 cruciferous plant, the shepherd's purse, when it is realised 

 that the species can be segregated into several elementary 

 species or biotypes. The latest investigation, undertaken 

 by Mr. G. H. Shull at the Station for Experimental Evolu- 

 tion of the Carnegie Institution of Washington, and de- 

 scribed in Publication No. 112 of the institution, bears 

 evidence with regard to the existence of at least four 

 biotypes which breed true under ordinary conditions and 

 can readily be crossed ; they are distinguished by charac- 

 teristic lobings of the leaf. The author has also investi- 

 gated the type known as Bursa {Capsellaj Heegeri, which 

 bears round seed capsules ; this plant was found in the 

 market-place at Landau, Germany, but has been lost except 

 under cultivation. 



Black spots varying in size from i/io-inch to 3/8-inch in 

 diameter are occasionally noticed on chilled beef. Dr. 

 Klein has investigated their nature, and finds them to be 

 caused by the mycelium of a fungus, an oidium, which is 

 quite harmless and does not alter the meat beyond their 

 limits (Report to the Frozen Meat Trade Association). 



An interesting contribution to the September number of 

 Travel and Exploration is an account, by a writer calling 

 himself " Pousse Caillou," of the region known as Chang- 

 chenmo, the home of the Tibetan antelope (Pantholops 

 liodgsoni) and the Ovis amnion, which lies north-east of 

 Leh, on the Kashmir-Turkestan frontier. Here we find 

 seventy or eighty miles of the most utterly forsaken 

 country which can be imagined. The lower volcanic hills, 

 broken into Gothic pinnacles, are backed by a coal-black 

 precipice, featureless and rigid in outline, while the inter- 

 vening valleys of pure sand are swept by bitterly cold 

 winds. Game preservation is more rigidly enforced even 

 than in Ladakh, only six licences for shooting being 

 granted annually, and the bag of antelope is limited to six 

 specimens. The writer vividly describes the difficulty of 

 shooting this shy animal, the success of the stalk being 

 often interfered with by the appearance of the kyang, 

 half-wild horse or ass, which roams wild on these 

 plateau.x. 



The report of the committee on ancient earthworks and 

 fortified enclosures, prepared for presentation to the 

 Congress of Arch;cological Societies for the current year, 

 presents no features of startling novelty. Measures for 

 protection of sites have been successful in the cases of 

 Maiden Castle, Dorset; Thetford Castle Meadow and Hill, 

 Norfolk; Stokeleigh Camp, on the Somerset side of the 

 Avon ; White Barrow, Wilts ; the earthwork at Selsea ; 

 the old landmarks of Epping Forest ; and Pendina's Camp, 

 Cardiganshire. On the other hand, the committee has to 

 report that in many cases the laying out of golf courses 

 has caused the mutilation of ancient ramparts and ditches. 

 The discovery of a portion of the Roman Wall of London 

 on the site of Christ's Hospital; excavations at Caerwent 

 and Caerleon, Caersws, in Montgomeryshire, and Elslack. 

 near Skipton, in Yorkshire, were the most important opera- 

 tions of the year. The bibliography of current literature 

 on the subject is a useful addition to the report of this 

 committee. 



It very rarely happens that three well-developed typhoons 

 occur within the space of ten days; in the Bulletin of the 

 Manila Weather Bureau for October, 1908, Senor Coronas 

 gives an excellent discussion, with charts, of three such 

 cyclonic storms which reached the central and northern 

 parts of Luzon on October 4, 8, and 13, accompanied by 

 photographs of the destruction caused. They all appear 

 to have originated in the vicinity of the Western Caroline 

 NO. 2081, VOL. 81] 



Islands, and to have travelled in a W.N.W. direction ; on. 

 reaching the archipelago they were considerably modified 

 in shape and extent, and crossed the China Sea in a 

 somewhat more northerly direction. The rates of transla- 

 tion, during which the wind at times reached hurricane 

 force, varied considerably, in one instance attaining the 

 unusual speed of twenty-one miles an hour, but on reach- 

 ing the China Sea the velocity of translation considerably 

 diminished in all cases. The barometric fall was very 

 rapid, the minimum at one station being 2799 inches, 

 although it was some fifteen miles from the vortex. Fore- 

 warned by valuable observations from Guam (Ladrone 

 Islands) and Yap (Western Caroline Islands), the Manila 

 Observatory was able to give timely notice in each case 

 to its own stations and to foreign services. 



Some interesting results are described and illustrated by 

 Dr. A. S. King in No. i, vol. xxx., of the Astrophysical 

 Journal, where he publishes a paper on the Zeeman effect 

 in the spectrum of titanium. The experiments were carried 

 out at the Mount Wilson Observatory, field strengths of 

 12,500, 13,800, and 18,400 gausses being employed between 

 the poles of a Du Bois electromagnet ; the dispersion used 

 was, generally, such that there were 0-93 Angstroms per 

 mm., the spectrograph being the 13 feet vertical Littrow. 

 A table, containing nearly 300 lines, between A 3904 and' 

 \ 6556, gives a summary of the results, and shows that 

 I the great majority of titanium lines are resolved into 

 triplets. Notable among the exceptions are the lines at 

 \ 4527-49 and \ 4544-.S6, each of which is resolved into 

 seven components, and shows a regularity of structure 

 identical in both ; the line at A. 4281-53 has eight com- 

 ponents. Two sextets and three quintuplets also show a 

 certain regularity in their separations, which is not shown, 

 however, by the lines having four components. Special 

 attention was paid to the forty-four lines given in 

 Lockyer's list of " enhanced " titanium lines, which do 

 not appear to fall in any special class ; thirty-five are 

 triple, six are quadruple, one quintuple, and two sextuple. 

 Two plates, which accompany the paper, beautifully illus- 

 trate some of the more interesting separations. 



Attention is directed by Mr. G. N. Huntly, in a brief 

 paper in the Journal of the Society of Chemical Industry, 

 to a curious case of corrosion occurring in a stand-by boiler 

 at the generating station of the London Electric Supply 

 Corporation. The corrosion had been noticed two years 

 previously, but attempts to check it by the addition of 

 caustic soda to the boiler-water had proved unavailing. 

 The interior of the boiler showed numerous blisters up to 

 30 mm. in diameter, most of them near the water-level ; 

 each blister contained a clear liquid with a black powder 

 in suspension, and a pit was observed to be forming in 

 the centre of each blister. Analysis showed the presence 

 of ferrous sulphate and free sulphuric acid in the liquid 

 contents, although the boiler fluid was alkaline and con- 

 tained little sulphur. The action was traced to manganese 

 sulphide in the steel, which had become oxidised with 

 formation of sulphuric acid ; as the water in the boiler 

 was quiet, the acid remained trapped behind a film of rust, 

 and acid corrosion could thus take place in an alkaline 

 medium, the oxygen required to convert the sulphur into 

 acid penetrating the blister more readily than the alkali 

 of the water. Addition of sodium arsenite to the boiler- 

 water in place of caustic soda completely stopped the 

 trouble, perhaps by eliminating the dissolved oxygen. 

 These experiments confirm the growing impression that 

 the injurious effects of sulphur in steel cannot be wholly 

 removed by the addition of manganese; so far from being 

 harmless, the manganese sulphide appears to be a 



