6oo 



NA TV RE 



[October 19, 1893 



plied to the borough. The Huddersfield installation is not yet 

 completed, but a portion of it is ready, and is now in actual 

 operation. When complete it will consist of an oxygen plant 

 and four bays of oil -gas retorts, capable collectively of producing 

 200,000 cubic feet of oxy-oil gas per day, together with the 

 necessary condensers and holders. The oxygen plant has been 

 already erected by Brin's Oxygen Company, and is their newest 

 type of producer. It is built in two sections, which 

 may be worlied together or independently, and will make 

 no less than 30,000 cubic feet of oxygen per day. This, 

 the largest oxygen-producer ever constructed, is now 

 in active operation. Of the oil gas plant one bay, consisting 

 of fifteen cast iron retorts, is also working, and is capable of 

 producing 50,000 cubic feet of oil gas per day. The lowest and 

 hottest of the retorts are intended for "cracking " the residues 

 from the upper retorts, but they may of course be fed with 

 clean oil if required. The oxygen is introduced into the oil gas 

 soon after the latter leaves the retorts and while still warm ; 

 the mixed gases then pass together through the condensers. 

 The admission of the oxygen is automatically adjusted by means 

 of a combination of meters, so that the proportion is constantly 

 maintained at fifteen per cent. The oxy-oil gas is stored in 

 special holders, and it is arranged to admit it into the coal gas 

 just before the entry of the latter into the station meter, the 

 quantity being regulated by a meter coupled to the station meter. 

 The results so far attained are highly satisfactory. The ad- 

 mission of about six per cent, of oxy-oil gas is already found 

 to increase the illuminating power of the corporation gas by 

 the equivalent of five and a half candles, and this is probably 

 much below the enrichment which will eventually be attained 

 when the plant is complete, and when normal coal can again be 

 employed at the cessation of the strike. The results attained 

 by the Salisbury Square plant are considerably superior to this, 

 and it is expected that the Huddersfield installation will even- 

 tually attain the same standard. Further, a marked increase 

 in the stability of the gas is observed, for poor coal gas actually 

 loses more illuminating power by storage than the same gas 

 admixed with oxy-oil gas does. As regards cost, it is calculated 

 from the experimental data furnished by the working portion 

 of the Huddersfield installation, that the increased cost of 

 production of the gas so enriched will not, at the highest 

 estimate, exceed a third of a penny per thousand cubic feet. 



Notes from the Marine Biological Station, Plymouth. — Last 

 week, like its immediate predecessors, was characterised by 

 stormy weather, which confined the dredging operations to 

 inshore areas. The chief capture was a large haul of the 

 Opisthobranch Oscaiiius {Pkttrobranchtis) membranaceits. The 

 approach of winter is already indicated in the bottom fauna : 

 colonies of the Compound Ascidian Fragarium elegaiis have 

 been frequently taken in their state of " hibernation," and the 

 colonies of the Polyzoan Btigula turbinata, which in the summer 

 orms extensive forests on the stones in certain areas, have now 

 almost completely died down. The Nemertine Amphiporits 

 dissimulans has begun to breed, and the greater number of 

 Micrura fasciolala are full-grown and sexually mature. 



The additions to the Zoological Society's Gardens during 



the past week include two Sykes's Monkeys (Cercopitliecus 



Ibigularis, 9 $ ) from West Africa, presented by Mr. W. H. 



Barber ; a Thick-furred Capuchin ( C«^af vellerosus) from South 



America, presented by Mr. R. Kettle ; three Tigers {Felis 



tigris, (5 ? 9) from India, presented by H.R.H. Princess 



Beatrice ; a Senegal Parrot (Pyocephalus senegalus) from West 



Africa, presented by Mrs. Rylands ; a Ruddy-headed Goose 



ernicla ricbidiceps, i ) from the Falkland Islands, presented 



y Mr. Henry Phillips ; a Tuatera Lizard [Sphenodon punc- 



tus) from New Zealand, presented by Mr. C. Stonham, 



NO. 125 I, VOL. 48] 



F.Z. S. ; a Diamond Snake {Morelia spilotes) from New South 

 Wales, presented by Mr. Arthur W. Darker ; a White-fronted 

 Lemur (Lemur albifrons) from Madagascar, two Common 

 Squirrels {Sciurus vulgaris, albino) British, deposited ; two 

 Blue - winged Teal (Querquedula cyanoptera) from South 

 America, a Japanese Teal [Querqtiedula formosa) from North- 

 east Asia, a Himalayan Monaul {Lophophorus impeyanus) from 

 the Himalayas, a Turnstone (Strepsilas interpres), a Curlew 

 ( Vnmenius arguala) European, purchased ; a Molucca Deer 

 (Cervus tiioluccensis) born in the Gardens. 



OUR ASTRONOMICAL COLUMN. 



The Scintillation ok Stars. — Though the question as 

 to the cause of the scintillation of stars has not received the 

 attention of many workers, yet it has had and still retains its 

 adherents. In a recent number of the Revue Scientifique, M. 

 Dufour gives the results of observations commenced in the 

 year 1853. The observations were made with the naked eye, 

 and were continued in all seasons and in all conditions of 

 the weather, since the chief object of the investigation was 

 to find out whether there was any relation between the 

 scintillations of stars and the disturbances which occur in 

 our atmosphere. The first results which were obtained led 

 to the forming of the following laws. (1) That red stars 

 scintillate less than white stars. (2) The intensity of the scin- 

 tillation is nearly proportional to the product obtained by mul- 

 tiplying the astronomical refraction for the height at which the 

 star appears, by the thickness of the stratum of air traversed by 

 the luminous ray that one is considering, and (3) that the causes 

 of some of the essential differences between the scintillations 

 of different stars may perhaps be due to the stars themselves. 

 Experiments for studying the question as to whether there was 

 any difference between the scintillation on mountains and upon 

 the plain, showed that on the mountains the scintillation was most 

 feeble. An important meteorological conclusion, which, as M. 

 Dufour says, is contrary to general opinion, and which he de- 

 duces from his numerous observations, is that a feeble scintilla- 

 tion generally announces the approach of bad weather. He 

 gives many instances in support of his view, among which 

 occur the observations at Col du Geant on July 12, 17S8, when 

 the brightest stars in Lyra, Cygnus, and the Eagle at the 

 same altitude showed practically no signs of scintillating, while 

 the next day there broke out over France the most violent storm 

 that the annals of meteorology had ever registered. M. Dufour 

 compares his work with that of M. Montigny, who commenced 

 work after him, and who was led to the same three laws above 

 mentioned. He suggests that as his observations were made 

 in Switzerland, it would be interesting to find out if afeebleness 

 of scintillation observed at sea also indicates bad weather. 



A Universal Telescope Stand. — The construction of a 

 good and simple universal mounting for small telescopes has been 

 the aim of many instrument makers, and it is pleasing to note 

 an advance in this direction made by the firm of K. Fritsch, 

 formerly Prokesch, in Vienna. In their new so-called 

 " Universal statio" they have overcome many of the main 

 difSculties. The chief point about this special kind of mounting 

 is that the observer can either use the telescope as a theodolite— 

 that is, with circles reading altitude and azimuth — or, by a slight 

 adjustment, he may have the equatorial mounting where the 

 circles read right ascension and declination. This end is 

 gained by hinging what would be the polar axis on to a 

 pivot at the side of the stand, thus allowing the axis to 

 be moved from the horizontal to the vertical or any inter- 

 mediate position. A strong metallic arc fixed on the top 

 of the stand supplies a means of clamping this axis, and 

 giving it a slight adjustment. With the axis vertical, we 

 have then practially a theodolite mounting; with the axis out 

 of the vertical, a parallactic mounting. It is needless to say that 

 this mounting is only for small telescopes, and indeed its 

 application to large ones is not needed. A detailed account of 

 the mounting, with figures, will be found in No. 20S of 

 Prometheus. 



Popular Astronomy. — Some time ago we inserted a note 

 in this column to the effect that the editors of Astronomy and 

 Astro-Physics, if they received sufficient support, would publish 

 a monthly journal — Popular Astronomy — written especially for 



