May 28, 1903] 



NA TURE 



89 



The extraction of the perfume from flowers such as 

 jasmine, tuberose, violet and cassia has long been carried 

 out by the process of enfleurage, the blossoms being left 

 in contact with purified lard for a few days, and then re- 

 placed by fresh blossoms. The lard is either sold as such, 

 •or the essential oil may be extracted from it by melting it 

 ■under strong alcohol. As the process of enfleurage is 

 somewhat tedious, attempts have frequently been made 

 to extract the oil directly from the flowers by means of 

 light petroleum, but these processes have not as a rule 

 proved successful, and it has recently been found that a very 

 large proportion of the perfume is actually produced for 

 the first time in the blossoms during the time occupied by 

 the enfleurage. An interesting illustration of this is given 

 by Dr. .Albert Hesse in a recent number of the Berichte, in 

 which he states that a ton (looo kilos.) of tuberose blossoms 

 only yielded 66 grams of oil when extracted with light 

 petroleum, but during enfleurage yielded 8oi grams of 

 ■oil to the fat in which they were embedded, whilst a further 

 78 grams remained in the faded blossoms and could be 

 separated by extraction or distillation. It thus appears 

 that eleven times as much perfume is produced during en- 

 fleurage as is originally present in the flowers, and that 

 ■even after enfleurage the exhausted flowers contain more 

 perfume than when first gathered. 



The additions to the Zoological Society's Gardens during 

 the past week include a Macaque Monkey (Macacus 

 4:ynomolgus) from India, presented by Captain Lambert 

 Larking ; a Naked-footed Owlet {Athene noctua) from 

 Holland, presented by Mr. R. Souper ; a Common Cormor- 

 ant (Phalacrocorax carbo), British, presented by Mr. C. F. 

 McNiven ; a Nilotic Trionyx {Trionyx niloiicus) from West 

 Africa, presented by Mr. Henry Reeve ; a Common 

 Chameleon (Chamoeleon vulgaris) from North Africa, pre- 

 sented by Mr. M. J. Comyn ; three Suricates (Suricata 

 tetradactyla) from South Africa, ten Black-spotted Lizards 

 {Algiroidcs nigro-punctatus) from Madeira, deposited ; a 

 Thar {Hemilragus jemlaica), a Burrhel Wild Sheep {Ovis 

 hurrhel), born in the Gardens. 



OUR ASTRONOMICAL COLUMN. 



Astronomical Occurrences in June: — 



June 3. Predicted perihelion passage of Faye's comet. 



,, I5h. Mars in conjunction with moon. Mars l° 49' N. 



8. I2h. lom. Minimum of Algol (.3 Persei). 



15. Venus. Illuminated portion of disc = o-6l3, of Mars 



=^0-885. 



,, iih. Uranus in opposition to the Sun. 



17. Juno 1° N. of /i Serpentis (mag. 36). 



■■,, I4h. Jupiter in conjunction with the moon. Jupiter 



3" 7' s. 



19. iih. 31m. to I4h. 55m. Transit of Jupiter's Sat. IV. 



(Callisto). 



20. I2h. 52m. Transit (egress) of Jupiter's Sat. HI. 



(Ganymede). 

 22. 3. Sun Enters Gemini. Summer commences. 

 27 9h. 28m. to loh. 5m. Moon occults a Cancri (mag. 

 4-3)- 

 ,, I3h. 36m. to i6h. 46m. Transit of Jupiter's Sat. HI. 



(Ganymede). 

 ,, i6h. Mercury at greatest elongation 22'" 5' W. 



Varhbility of Nova Geminorum. — A note from Prof. 

 E. C. Pickering which appears in No. 3868 of the Astro- 

 nomischc Xachrichten states that the light of Nova 

 Geminorum appears to be fluctuating in a manner similar 

 to that of Nova Persei, No. 2. During the twenty-four 

 hours preceding the evening of May 1, it had increased by 

 half a magnitude. 



NO. 1752, VOL. 68] 



The nature and amount of these fluctuations will be seen 

 from the following table of measures made at Harvard : — 



Origin ok the H and K Lines of the Solar Spectrum. 

 — In a paper communicated to the April number of the 

 American Journal of Science, Prof. J. Trowbridge, of 

 Harvard University, gives the results he has obtained from 

 a series of careful experiments which he made in order to 

 determine the constitution of the H and K lines in the 

 solar spectrum, and also discusses the nature of reversed 

 lines in gaseous spectra. 



By a series of preliminary experiments he arrived at the 

 conclusion that the lines which he obtained coincident with 

 the calcium lines were not due to any calcium in the glass 

 tubes or the terminals used in obtaining the spark, and 

 further he argues that, even if the glass did contain 

 calcium, the duration of the spark was not sufficiently long 

 to raise the temperature of the glass high enough for it 

 to produce a spectrum, whilst in obtaining his spectra he 

 photographed a part of the spark which was far enough 

 removed from the terminals to ensure the absence of 

 metallic particles ejected by them. 



Using quartz tubes sealed by metallic ends he obtained 

 the reversed line at \ 4227, and also lines coincident with 

 the solar lines 3968 and 3933, quite as strong as wften a 

 glass tube was used, whilst the other strong calcium lines 

 towards the ultra-violet were conspicuously absent. 



Prof. Trowbridge found that the spectra obtained from 

 a highly disruptive spark discharge between electrodes of 

 some metals do not show these lines, whilst those obtained 

 from a similar spark between other metals, e.g. pure 

 silver, platinum and iridium, do show them ; he suggests 

 that in the former case the metals are easily volatilised, and 

 their vapours conduct the spark, whereas in the case of the 

 latter class of metals the air conducts the discharge because 

 no metallic vapours are produced, and therefore it is some 

 gaseous constituent of the atmosphere which produces the 

 lines in question. For similar reasons he believes that 

 some lines at present attributed to silicon — another highly 

 refractive substance — are possibly atmospheric. 



From these observations Prof. Trowbridge arrives at the 

 following conclusions : — " At the basis of the great H.H 

 lines of the solar spectrum there are strong gaseous lines 

 which I believe to be oxygen lines. The reversed lines 

 which apparently coincide with certain calcium lines are 

 not due to calcium but are gaseous." Reproductions of 

 four spectrograms, which accompany the article, illustrate 

 the reasons for these conclusions. 



The Leeds Astronomical Society. — The tenth annual 

 issue of the Journal and Transactions of this Society con- 

 tains a series of useful papers which were communicated 

 to the Society by its members during 1902. Amongst others 

 there are papers on " Parallax," " Velocities, Paths and 

 Kclipses in the Solar System " (illustrated by diagrams of 

 the various orbits), " The Age of the Earth," " Brightness 

 and Definition," and " The Year's Observations" (which 

 were in the most part observations of Jovian phenomena), 

 all of which should prove of value and interest to amateur 

 astronomers. 



The Journal concludes with a collection of the papers and 

 letters communicated to other journals by the members of 

 this Society during 1902. 



THE ADVANCEMENT OF PHOTOGRAPHY. 



A T the recent meeting of the Royal Photographic Society 

 ■^^ held to celebrate its jubilee, the president. Sir William 

 .Abney, K.C.B., F.R.S., suggested, in an address of which 

 an abridgment is given below, that the Society should 

 further mark the close of the first fifty years of its existence 

 by establishing laboratories and suitable accommodation for 

 the carrying out of photographic researches. A donation of 

 looZ. has already been promised, on condition that 900/. 

 more is raised for this purpose. The establishment of such 

 facilities is highly desirable, for, excluding the work of a 

 few whose names may be counted on the fingers of one 



