November 7, 1901] 



NATURE 



Several new editions of scientific books of established 

 reputation have recently been received. The fourteenth edition 

 of Naumann's well-l^nown " Elemente der Mineralogie," edited 

 by Prof. F. Zirkel, has been published by Mr. Engelmann, 

 Leipzig (London : Williams and Norgate). The book stands in 

 the first rank of treatises on mineralogy, and is likely to main- 

 tain this position while it is so well kept in touch with scientific 

 progress by revised editions. — A similar standard work is Gray's 

 ''Anatomy: Descriptive and Surgical," the fifteenth edition of 

 which, edited by Messrs. T. Pickering Pick and R. Howden, 

 has been published b y Messrs. Longmans, Green .^nd Co. The 

 entire work has undergone revision, and the section on embry- 

 ology has been considerably amplified. The volume will thus 

 secure the attention of students for some time to come. — The 

 third edition of Prof. A. H. Church's " Chemistry of Paints and 

 Painting " has been published by Messrs. Seeley and Co. An 

 elaborate and appreciative review of this book appeared in these 

 columns nearly ten years ago (vol. xlv. p. 243). The plan 

 remains the same as in the first edition, but many slight changes 

 have been made and new pigments, or new varieties of old 

 pigments, are described. In the four last chapters Prof. 

 Church gives "adequate evidence of the instability of several 

 favourite pigments largely used by painters in water-colour 

 during the eighteenth and nineteenth centuries." — .\Ir. Walter 

 Scott has published the third edition of Mr. Havelock Ellis's 

 book on "The Criminal," which was reviewed in these columns 

 when the first edition appeared (vol. xlii. p. 75, 1890). Since 

 then increasing attention has been given to criminal anthropology, 

 and Mr. Ellis gives a valuable statement of the present 

 position of the subject. His book has been enlarged by more 

 than one hundred pages, and much new material has been 

 examined and summarised. 



We have received a copy of Prof. Letts' report on the 

 scheme of sewage purification for Belfast and its probable 

 effects on the Lough. In this report Prof. Letts first deals in a 

 simple way with the chemical nature of sewage and the various 

 methods of sewage disposal. He then deals with the subject of 

 the vast deposits of sea-lettuce ( Uha latissima) which accumu- 

 late on the Belfast foreshore and, undergoing decomposition, 

 produce serious nuisance. It is shown that the development of 

 the sea-lettuce, which is extraordinarily rich in nitrogen, is 

 associated with the presence of sewage in sea-water and that it 

 thrives wherever an ordinary sewage effluent escapes into sea- 

 water. Coming next to the proposed method of treating the 

 Belfast sewage by double contact with bacteria beds and the 

 discharge of the resulting effluent into the Lough, Prof. Letts 

 concludes from his experiments that the bacteria beds are 

 dispersers rather than converters of nitrogen, that is to say, they 

 liberate a large proportion of sewage nitrogen in the gaseous 

 form. Hence the efiluent from such beds is unlikely to stimulate 

 the growth of the noxious green seaweed, and Prof. Letts con- 

 siders it probable that the proposed system of sewage treatment 

 will eventually suppress the growth sufficiently to put an end to 

 the existing nuisance. In a series of recommendations ap- 

 pended to his report, Prof. Letts suggests the reclamation of 

 large tracts of foreshore and more systematic removal of the 

 decomposing weed. He thinks it probable that by allowing 

 the sewage effluent to flow into tidal ponds containing sea-water 

 and sea-lettuce the nitrogen content might be reduced almost to 

 the vanishing point. The lettuce could be regularly removed 

 and used advantageously as a manure. 



The additions to the Zoological Society's Gardens during the 

 past week include a White-fronted Capuchin (Cebm hypokucus) 

 from Central America, presented by Mr. G. B. Apostoloff; two 

 Syrian Bulbuls (Pycnonolus xanthopygos) from "Tayif, Arabia, 

 presented by Mr. G. P. Dovey ; a Hocheur Monkey {Cerco- 

 pilkecus nictitaits, 9 ) from West Africa, a Simpae Monkey 

 NO. 167 I, VOL. 65] 



(Seinnopithicus inelaiaphus, S ) from Sumatra, three Ogilby's 

 Rat Kangaroo {Bettongia penicillata) from Australia, a Zebra 



{Equus (5 ), four Young V\an^{Felis ko, i i i i),^. Caracal 



(Felts caracal) from Abyssinia, an Indian Antelope [Antilope 

 cervicapra), a Ruddy Ichneumon (Herpesles smithi) from India, 

 a Goshawk {Astiir palumharius), European ; five Smooth- 

 clawed Frogs (Xenopus laevis) from Africa, deposited ; twelve 

 Changeable Troupials (Qiiiscahts versicolor), six Painted Terra- 

 pins (Chrysemys picta), two American Box Tortoises ( C«i/«afff 

 Carolina), a Copperhead [Ancislrodon conlorlrix), two Horrid 

 Rattlesnakes (Cro/alns horridus) from Pennsylvania, three 

 White-eyebrowed Finches {.Zonotrichia leucophrys), three Lark 

 Buntings {Calamospiza bicolor), three Mexican (Quails (Calli- 

 pepla squamata), two Painted Box Terrapins (Cistudo oriiata), 

 five Poinsett's Lizards {Sceloporus torquatus, var. poinselti), ix 

 Lesser Horned Lizards [Pkryiiosoina modestuin), a Say's Snake 

 (Coluber catenifer, var. sayi), a Confluent Rattlesnake (Crotalus 

 confluentus), two Testaceous Snakes [Zamenis flagelliformis), 

 two Western Diamond Rattlesnakes (Crotalus atrox) from 

 Pecos, Texas ; two Common Rattlesnakes (Crotalus dtirissus), 

 two Couper's Snakes (Spilotes corais, var. couperi) from Marion 

 CO. , Florida, received in exchange. 



OUR ASTRONOMICAL COLUMN. 



The Period of Algol. — Prof. S. C. Chandler has made a 

 further investigation of the minor inequalities of the period of 

 Algol. These have probably escaped notice up to the present 

 owing to their being so minute as to be of the same order as the 

 errors of observation. 



This later inquiry indicates that the deviations of the observed 

 from calculated times of minima have been periodic, distinct 

 changes occurring in the course of a few months, but it does not 

 appear that the periodicity is of a regular character. More fre- 

 quent and continuous observations of the minima, however, are 

 required to decide this question. 



It appears from the curves representing these minor in- 

 equalities that the length of the principal of them is about 

 15,000 periods, this period from the most recent computations 

 being 



2d. 20b. 48m. 55'6o5. -f 



3-6945. sin (133" - 0^-024 E.) 4- 1784'- sin (16' - iV° E.) 



Tables are then given showing the influence of including 

 these new terms in the comparison of observed with computed 

 epochs of minima (Astronomical Journal, vol. xxii. pp. 39-42, 

 1901. 



The Melbourne Observatory. — The annual report of 

 Mr. P. Baracchi, the Government astronomer at Victoria, has 

 recently been issued. All the usual routine work in astronomy, 

 meteorology, terrestrial magnetism, &c., has been carried on as 

 usual, and considerable progress has been made in the 

 endeavour to lessen the accumulated arrears of unreduced 

 records. 



With the astrographic instrument 261 plates have been 

 obtained, including 63 chart triple exposures, 49 chart single 

 exposures, and 39 catalogue plates. The chart series of single 

 exposures of 60 m. is now complete. The new Repsold micro- 

 meter made from the designs of Sir David Gill is found to 

 work very satisfactorily, and measurements are made at twice 

 the former speed, dealing with about 170 stars per hour. 



The Milne seismograph is now adjusted in position and a 

 continuous photographic record of seismic disturbances will be 

 started as soon as possible. 



Royal Alfred Observatory, Mauritius.— The annual 

 report of Mr. T. F. Claxton, director of the Royal Alfred 

 Observatory, has recently been distributed, giving details of 

 progress made during the year 1900. The meteorological and 

 magnetic observations have all been continued as in previous 

 years, but much of the astronomical work with the prime 

 vertical and equatorial had to be abandoned on account of the 

 unhealthiness of the district. Photographs of the sun with the 

 photoheliograph were taken whenever weather permitted, and 

 311 negatives with 301 prints were forwarded to the Solar 

 Physics Committee. 



