August 23, 19 17] 



NATURE 



1 1 



cated by Th. Hesselberg and H. U. Sverdrup, and T. 

 Oaarder writes on oxygen in the fjords of Vestland. 



It is not generally recognised that the common 

 British ragwort {Senecio Jacohaea, L.) is poisonous 

 to cattle. Such would appear to be probable, however, 

 from cases which have recently been investigated in 

 the veterinary laboratory of the' Board of Agriculture, 

 and form the subject of a note in the Journal of 

 the Board for July. Under natural conditions the 

 poisoning is a slow process, but with continuous doses 

 the amount of poison which becomes available is suffi- 

 cient in time to cause very serious symptoms, which 

 •often end in death. In one case quoted visible 

 symptoms of poisoning were not obser\ed until fort>'- 

 four days after feeding on ragwort commenced. No 

 ■cure has yet been devised, and prevention resolves 

 itself into removing the ragwort from the forage or 

 ■eradicating it from the pastures. The winter and 

 ■early spring grazing of infested land with sheep has 

 been recommended for this purpose, and has been 

 practised apparently without harmful results. It would 

 be unsafe, however, to conclude from this that sheep 

 are immune to poisoning by ragwort, since there is 

 reason to think that the fiowermg season — June to 

 August — is the time of greatest danger. This aspect 

 •of the matter is receiving further attention. 



The Journal of the Royal Agricultural Society of 

 England for igiS (vol. Ixxvii.) presents the usual 

 features of special articles, notes, and official reports, 

 although for obvious reasons the number of special 

 articles is somewhat curtailed in comparison with past 

 volumes. Dr. Russell and Mr. E. H. Richards con- 

 tribute an article on making and storing farmyard 

 manure, which outlines various results of interest both 

 for practice and for science obtained in recent investi- 

 gations at Rothamsted. Attention is again directed to 

 palm kernel cake and meal by Prof. C. Crowther, in 

 a summary of existing information as to the nature, 

 use, and merits of these materials as food for stock. 

 An interesting article on the origin and character- 

 istics of Welsh black cattle is contributed by Prof. 

 C Bryner Jones. The annual reports of the scientific 

 advisory officers of the society contain, as usual, many 

 matters of interest, of which we may note Sir John 

 McFadyean's account of results obtained at the Royal 

 Veterinary College in the investigation of Johne's 

 disease, and Mr. Cecil Warburton's summary of the 

 present state of knowledge concerning the ox warble- 

 fly. 



Various matters of immediate interest to agricul- 

 turists are dealt with in Occasional Notes, No. 2 (July, 

 1917), issued by the Royal Agricultural Society. The 

 general scope and arrangement of the opening number 

 of this new series are retained, the various advisory 

 officers of the society contributing the different sections 

 into which the notes are classified. The notes are 

 ■essentially practical, dealing, amongst other matters, 

 with the growing of wheat, the raising of farm seeds, 

 plant pests, motor tractors, and calf-rearing. 



Ix the Rendiconti del R. Istituto Lombardo, vol. 1. 

 {2) 6, Prof. Torquato Taramelli discusses the origin of 

 the deposits of sand found in the island of Sansego 

 and other islands off the Istrian coast, and finds geo- 

 logical arguments in favour of Italy's claims to terri- 

 tory which is the scene of the present military' opera- 

 tions. Among the numerous papers previously dealing 

 with the geological features of the islands of the 

 Quarnero basin many references occur to deposits of 

 sand and red earth, but Prof Taramelli occupies him- 

 self mainly with the mass of sand overlying a cal- 

 careous base, which forrris the island of Sansego. 



NO. 2495, VOL. 99] 



This island has a surface area of about three square 

 kilometres and a circumference of about seven kilo- 

 metres, and is the outermost island of the Quarnero 

 archipelago. In its composition this sand is largely 

 identical with that deposited by the river Po off the 

 Italian coast, while nothing similar is to be found 

 in the neighbouring Austrian mainland. It is thus in- 

 ferred that in the Quaternary period the northern por- 

 tions of the Adriatic were occupied by a vast river 

 basin of Italian origin, and that the natural frontier 

 of Italy, based on geological considerations, extends up 

 to the confines of this basin. 



Dr. L. F. Navarro contributes to the Revue 

 gindrale des Sciences, 1917, p. 263, a most useful 

 and interesting summary of what is known as to 

 glacial phenomena in the Iberian peninsula. He 

 points out that well-founded evidence of glaciation in 

 this area, outside the Pyrenees and certain high 

 chains, was brought forward for the first time by 

 W. Halbfass so recently as 1912. The references to 

 literature, including the author's own work, show 

 how rapidly observation is progressing. No general 

 mantle of ice has been traced, even in the Cordilleras; 

 but a sheet of some magnitude, here called "mm grand 

 inlandsis," occurred in Leon. Two glacial episodes 

 are recognised, corresponding to the Riss and Wiirm 

 ages elsewhere in Europe. The author regards these 

 as times when the present conditions in tlfce peninsula 

 were exaggerated in the direction of greater humidity 

 and greater cold. Glacialists, however, are coming to 

 the conclusion that no great demands -need be made 

 upon humidity, provided that there is a sufficiently 

 low temperature. 



The revolution — a milder word would be inadequate 

 — in the position of the British optical industry' is one 

 of the commonplace changes brought about by the 

 war, and it is not surprising to find that the new 

 conditions are reflected in the growth of the Optical 

 Society, which is now thoroughly representative of 

 the industry and is rapidly becoming as fully repre- 

 sentative of those whose interest in optics has been 

 of a more theoretical character. Advantage has very 

 appropriately been taken of the improved outlook to 

 issue the society's Transactions at more frequent in- 

 tervals and in a new form. The first number of the 

 new series, of the same size as the Proceedings of the 

 Royal Society, is chiefly occupied with a paper bv 

 Mr. J. W. French dealing with the grinding and 

 polishing of glass. It is suggested that the processes 

 involved are essentially different from those which 

 apply in the polishing of metals. Evidence is brought 

 forward to sho\v'that, in the process of grinding, glass 

 is removed in consequence of the formation of con- 

 choidal fractures originating at the points of contact 

 of the glass and the abrasive, rather than by a plough- 

 ing action. Incidentally, an interesting method of 

 grading partially worked surfaces is described. The 

 first part of the polishing process consists in ploughing 

 up the soft surface layer of the glass, which has a 

 thickness of about eight wave-lengths, by coagulated 

 lumps of the wetted polishing medium until all the 

 material above the bottom of the deepest grooves has 

 been removed. In the second part of the process, 

 which begins when the water is allowed to drv up, the 

 surface layer of the glass is liquefied by the' pressure 

 of the pitch tool and caused to flow until the surface 

 becomes uniform. The paper is illustrated bv a large 

 number of excellent photomicrographs, and followed 

 by a discussuDn in which alternative theories are sug- 

 gested, and the views of some experienced glass- 

 workers are given. The number is attractively printed, 

 and gives an excellent start to a journal which should 

 play a large part in establishing the optical industry 



