254 



NA TURE 



[January 12, 1899 



By making use of the exceedingly low temperatures that can 

 now be obtained, a very simple method for exhausting X-ray 

 and other vacuum tubes presents itself. An example of this 

 was given by Prof. Dewar at a recent meeting of the Koyal 

 Society, at which he was able to produce an almost perfect 

 vacuum. By dipping the end of a closed tube filled with air 

 into liquid hydrogen, the air quickly condensed at the bottom in 

 a solid form. It then only remained to separate from the rest 

 that part of the tube from which the air had been so removed, 

 by healing and sealing ofif, and the lube was found to possess 

 an extremely high vacuum. In fact, so perfect was the vacuum 

 that it was difficult to pass an electric current through it. One 

 great advantage of this mode of procedure is that in the above 

 case only one minute w.as taken to obtain the required result. 



We regret to see, in the Electrical Review, the announcement 

 of the death of Dr. Eugen'F. A. Obach, at the comparatively 

 early age of forty-six years. He was born in Stuttgart, of Swiss 

 parents. In 1875 he obtained his degree of Doctor of 

 Philosophy at the University of Leipzig. After spending a few 

 years in electrical engineering, Dr. Obach devoted himself 

 mainly to the study of the chemistry of gutta-percha and india- 

 rubber, the result of his extensive and varied knowledge of these 

 substances being embodied in his Cantor Lecture delivered 

 before the Society of Arts. A long abstract of these lectures 

 appeared in Nature in June last (vol. Iviii. p. 136). Shortly 

 after that time his health liiiled, and even prolonged rest from 

 work brought about no improvement, and he died on December 

 27 at Graz, Styria. Dr. Obach had been a frequent contributor 

 to the literature of electrical science since 1875, about a score of 

 papers being published in the English and German technical 

 journals or in the Proceedings o{ic\e.w\\f\Q. societies. 



Dr. Reinhold Ehlert, distinguished by his studies in 

 seismology, has lost his life by an Alpine accident on the 

 Susten Pass. Among other valuable seismological works, he 

 wrote a treatise on "A comparison, explanation, and critical 

 estimate of the most important seismometers, with special 

 reference to their practical utility." This work was couronni 

 by the philosophical faculty of the University of Strasburg, 

 where Dr. Ehlert conducted his investigations. 



Reuter reports from Copenhagen that Captain Daniel 

 Brunn has decided to organise an expedition next summer to 

 search for traces of Ilerr Andree and his companions in the 

 neighbourhood of Eastern Greenland. The expedition will 

 start from the east coast of Iceland, and proceed by way of Jan 

 ALiyen Island to the vicinity of Cape Barclay, on the East 

 Greenland coast. 



The Pharmaceutical Journal reports the opening of a chemical 

 and pharmaceutical laboratory in Rajkote, the seat of the 

 Government in the province of Kalhiawar, Western India. 

 The building is the gift of Azam Laxmon Meram, who contri- 

 buted 30,000 rupees for its construction ; and its equipment has 

 been provided from the State Joint Fund. The object for which 

 the building has been primarily founded is for improving the 

 practice of native medicine and for making known valuable 

 Indian remedies to Western science, and also to ascertain which 

 native herbs may be made more adaptable to science ; and it is 

 hoped that eventually it may further the progress of bacteriology 

 and sanitary science. The director of the laboratory is Mr. H. 

 L. Lee. 



Tub present position of the Rontgen rays in military surgery 

 was described by Major J. Batlirsby in a paper read before the 

 Riintgen Society on Tuesday. Major Hatlersby was selected for 

 service in charge of the Rontgen ray apparatus in the Sudan, 

 where the temperature varied from 100 to 122 degrees F. in 

 the shade ; and his paper was based upon his experience in this 

 campaign. After the battle at Omdurman 121 British wounded 

 NO. 1524. VOL. 59] 



were conveyed to the surgical hospital at Abadieli. Of that 

 number there were 21 cases in which the bullet could not be 

 found, or its absence proved by ordinary methods. In 20 out of 

 these 21 c.ises an accurate diagnosis was arrived at with the help 

 of the rays, the odd case, who was suffering from a severe bullet 

 wound in the lung, being too ill for examination at the time. 

 The senior medical oflicer in charge of the hospital said : — " The 

 Rontgen rays proved of invaluable assistance in localising the 

 exact position of bullets, and in many cases rendered probing 

 of wounds unnecessary. . .. In many ca.ses the X-rays prevented 

 much sufifering to the patient, which would have been caused by 

 probing, the use of the finger, or enlarging the wound in the 

 ordinary search for the bullets, as the skiagraph at once indicated 

 the ex.act position of the bullet. In other more complicated cases 

 the Mackenzie-Davidson method localised the exact position of 

 the bullet, so that the surgeon was at once able to come to the 

 conclusion if operative interference was judicious or other- 

 wise. If considered advisable, the removal of the bullet 

 was much facilitated by the diagram previously indi- 

 cating exactly where the projectile was to be found.'" 

 With regard to apparatus, the most serious difticulty at preserjt 

 is the best method of generating the primary electrical current 

 for charging the storage batteries, or working the coil direct. 

 Primary batteries, for many reasons, are unsuitable and not to 

 be recommended. In the Sudan a small dynamo, driven by 

 means of a tandem bicycle, answered admirably, and was readily 

 transported by rail and river to Abadieh ; but as at present 

 constructed, it is unsuitable for mule, camel, or human 

 transport. An ideal apparatus would consist in a statical or 

 friction machine, some modification, for instance, of Mr. Wins- 

 hurst's, by which the focus tube could l)e excited direct. In 

 such a design many physical difficulties will occur, but they are 

 not insurmountable. If it is achieved, it will enable the present 

 apparatus to be reduced very considerably by dis|v;nsing with 

 primary and storage batteries, dynamos, bicycles, and induction 

 coils. 



With reference to the landslip from the Sasso Rosso, which 

 destroyed several buildings at Airoloon December 27, 1S98, the 

 Zurich corres|X)ndent of the Times states that Swiss geologists 

 are of opinion that the landslip is by no means over, and that a 

 mass of rocks equal to that which fell last week has yet to come 

 away. It is ho])ed that the detachment will take place ir> 

 smaller masses, and that no slip exceeding the |>resent (400,000 

 cubic metres in volume) is to be apprehended. The summit of 

 the Sasso Rosso is 2300 metres above the sea level, and 1200 

 above Airolo, and the falling rocks reached the village with a 

 velocity of 15 to 20 metres per second. The present danger 

 lies in the rocks which remain suspended on the flank of the 

 mountain. Should these give way, the village and the southeri* 

 exit of the tunnel would be endangered by the avalanche, a risk 

 which is increased by recent heavy rain and snow. Compared 

 with other similar avalanches, the amount of dtbris already 

 fallen is not excessive; at Elm the fall exceeded 11,000,000 

 cubic metres, at Goldau it was 25,000,000, and the historic 

 landslip at Brienz in 1749 was estimated at 50,000,000 cubic 

 metres. 



The New York Zoological Society has issued the third 

 number of its AV-c.t Hullclin, in which the progress of the 

 work of transforming .South Bronx Park into a Zoological Park 

 is described and illustrated. Seven months ago the New York 

 Zoological Park was a tract of wild land, but since then several of 

 the animal houses have almost been completed, and other en- 

 closures have been made. New \'ork City has voted 30,000 dollars 

 as a maintenance fund for six months, both for the care of the 

 animals and the care of the P.irk, and is expending 62,000 

 dollars in the development of roads, walks, drains, and other 

 ground improvements. It is a matter for congratulation that 



