Oct., 1904.] 



KNOWLEDGE & SCIENTIFIC NEWS. 



243 



A Scheme for the Comparison of 

 Climates. 



Is it possible to express the pU is.mtness or unploasaiitness 

 of .1 climate on a scientific scale ? Captain W. F. Tyler, 

 F.R.Met.Soc, has attempted to form such a scale. Con- 

 cluding that the two dominant factors intlucncing our sensa- 

 tion of comfort are temperature and huuiidity, he has coined 

 the word " hyther " — apparently from the first syllables of 

 "hygrometer" and "thermometer" — to indicate this joint 

 effect. .-V perfectly pleas.ant day is registered o on this hyther 

 scale, and an intolerably oppressive one as 10. Captain 

 Tyler's own observations of " hyther " extend over several 

 years, but in the end of the summer of 1902, he was able to get 

 the cc-operation of eleven other observers for the systematic 

 observation of "hyther" throughout the month of August. 

 The results of the comp.arison showed that most persons 

 would require a considerable amount of practice before their 

 observations could be considered trustworthy, but some 

 approach was made towards the establishment of a definite 

 law connecting the temperature and humidity witli the 

 hyther sensation. .-Vt the same time there were indications 

 that some other factors, possibly barometric pressure or electric 

 conditions, had an appreciable influence upon the sensation. 

 The subject seems well worth working out on a more extended 

 scale. 



* * * 



The Paris Observatory. 



The annual report of the I'aris Observatory for 1903, pre- 

 sented to the Council on March 22 of the prescut year, deals 

 with a number of researches of speci.al interest. The seventh 

 section of the Atlas of the Moon has appeared, containing 

 seven plates which seem the most successful yet issued, and 

 in some respects to show a considerable advance over the best 

 \-iews of the moon obtained by the eye at the telescope. With 

 respect to the .•^strographic Chart, eleven plates have been 

 passed as satisfactory, and thirty-five charts containing the 

 triple images of 47,300 stars h.ave been distributed. It is hoped 

 that the second volume of the Photographic Catalogue will 

 appear by the end of the current year. The determination of 

 the solar parallax from the photographic observations of Eros is 

 advancing towards completion. Of standard stars 1 66 1 meridian 

 observations have been made, and 10,858 photographic obser- 

 vations of comparison stars, of standard stars, and of stars 

 near the path of Eros, Three important researches based 

 upon new methods are included in the programme for the 

 future work of the observatory : the first relates to the deter- 

 mination of latitude and of its variations; the second is for 

 the precise determination of the constant of aberration, two 

 portions of the sky, distant go", being presented in the field of 

 the instrument at the same moment by means of a double 

 mirror; and the third relates to the employment of M. Lipp- 

 mann's photographic object-glass in meridian observations. 



* * * 



R^e= discovery of Encke's Comet. 



Encke's comet was re-discovered at the Kiinigstuhl Obser- 

 vatory on September ti at i3h. i6-gm. local mean time. Its 

 right ascension at discovery was i' 46' 16", and its declination 

 N. 25' 24'. This is the thirty-sixth return of the comet since 

 its discovery in 1786; the twenty-ninth during which it lias 

 been observed. 



BOTANICAL. 



By S. \. Skan. 



The Comptcs Rendiis, vol. cxxxvii., contains some valuable 

 observations on the germination of seeds of orchids by Mons. 

 N. Bernard, whose experiences warrant his making the inte- 

 resting and rather remarkable statement that germination, at 

 least in the case of some seeds of CattUya and LacUa with 

 which he experimented, is wholly dependent on the presence 

 in the embryo of a filamentous endophytic fungus. In a fort- 

 night after sowing the seeds some minute spherules, rendered 

 evident by their green colour, were produced. Some of the 



epidermal cells of these bodies elongated into short papillaj, 

 but did not form any true hairs. It was observed that in 

 aseptic sowings, even after the lapse of five montlis from the 

 time when the green spherules made their appearance, no 

 further development of the seeds had taken place. Many 

 were destroyed by mould, sooner or later. If, however, the 

 .seeds in the state indicated were transferred to a tube in 

 which was .a culture of a certain hyphomycelous fungus, 

 further growth almost immediately resulted, and it was found 

 that the hypha' of the fungus had penclr.ited the median part 

 of the suspensor and the adjacent cells of the embryo. In 

 fifteen d.ays the seedlings had assumed their characteristic 

 top-shaped appearance, developing a terminal bud and long 

 absorbing hairs. In the cultures, besides the fungus which 

 Mons. Bernard regards as necessary to germination, a 

 coccobacillus was present, but it did not appear to have any 

 effect, either in hindering or promoting germination; if, how- 

 ever, other fungi or bacteria were substituted for the particu- 

 lar kind of fungus found to be essential, the seeds, instead of 

 germinating, were destroyed. 



\ rose which h.as created a great deal of interest in horti- 

 cultural circles is the subject of one of the plates in the Sep- 

 tember number of the lUitanical Mai^azinc. The late Sir 

 H(;nry Collett met with this rose, to which he gave the name 

 of Rosa f;if;itiilcit, as a very striking object in the forests of the 

 Shan Hills in Northern lUirnia, and it was through him that 

 seeds were received .at the Royal Botanic Gardens, Kew, in 

 1888. No ditlii'ulty was experienced in getting the seeds to 

 germinate, and the seedlings soon developed into plants 

 remarkable for the enormous length of theu' shoots, one of 

 these in the Temperate House reaching a length of fifty feet. 

 N'isitors to the Succulent House may have observed the 

 robust specimen planted in the central bed there, which had 

 grown along the roof, and then out through a ventilator into 

 the open air. 15ut though growths were produced in almost 

 embarrassing freedom, no llowers have ever been borne by 

 the Kew plants. Indeed, it is believed that only in two 

 gardens in this country has the plant flowered at all. From 

 one of these — .'Mbury Park, Guildford — the material was 

 obtained from which the Dutanical Maf^azinc drawing was pre- 

 pared. The flowers are white, or white tinged with yellow, 

 and are from four to six inches in diameter. The same rose 

 was found first in Manipur, and it is now known to occur in 

 Western China. 



ORNITHOLOGICAL. 



By W. B. BvcR.MT. 



Brush Turkeys breeding in Confinement. 



Mk. BivRTLINg, in the August number of the A^'uiitlural 

 Magazine, concludes his notes on the breeding of the Brush 

 Turkeys ('ralci;alla UHluimi) in the Gardens of the /Zoological 

 Society. 



His account, though short, is extremely interesting and of 

 considerable scientific value. 



Some time since, these birds constructed a mound of the 

 usual type, and deposited therein a number of eggs. The 

 nestlings being overdue, it was at last decided to at lea.st par- 

 tially explore the mound, and this resulted in exposing three 

 eggs. These lay about one fool apart from each other, and some 

 18 inches from the surface. They were placed with the large 

 end upwards, and had certainly not been turned, as a deep 

 hole, of the shape of the egg, was left on its removal. More- 

 over, the egg did not touch the bottom of the hole, inasmuch 

 as the small end was quite white, whilst the rest of the shell 

 was stained by contact with the mould. 



A further search revealed a chick, evidently dazzled by the 

 sudden glare of the light. The "(|uills" of this bird were 

 nearly 3 in. long, and as it could fly fairly well, he says, 

 '■ 1 have come to the conclusion that the yoimg remain at 

 least 36 hours, or longer, in the mound before making their 

 appearance, as three others, hatched in an incubator, were not 

 nearly so advanced when hatched." 



The shell is very thin, so that the young do not chip round 

 the upper part of the egg in order to make their escape, but 



