228 



NATURE 



[July 5, 1888 



University. It may be interesting to record the results 

 of the computations so far obtained, viz. : — 



61 1 Cygni . 0*4289 ±0*0180 



61 2 Cygni . 0-4353 ±0-0152 

 Ij. Cassiopeise 0-0356 ±0*0250 

 Polaris . . 0*052 ±0-0314 



o Cassiopeise . 0*072 ±0-042* 

 P Cassiopeise . 0*187 ±0*039* 

 7 Cassiopeise<o*o5 ±0*047* 



The last result is peculiarly interesting, as it seems to 

 furnish an instance where the resources of modern 

 astronomy have arrived at the limits of their present 

 possibility. The total number of plates taken for the 

 purposes of the above investigation is approximately 700, 

 and each plate has been measured with 120 bisections of 

 the necessary stars, amounting altogether to about eighty- 

 four thousand observations. Independently and concur- 

 rently with the preceding work Dr. Pritchard undertook 

 for the Photographic Committee of the Royal Society the 

 examination of two silver on glass mirrors of the same 

 aperture but of very different focal lengths, with the view 

 of ascertaining the practical effects of focal length on the 

 photographic field. This work, owing to the temporary 

 character of the mounting and the imperfection of the 

 mechanical movement of the telescope, has been attended 

 with great labour and personal endurance on the part of 

 the observer, but at length it was brought to a successful 

 conclusion, and the results have been communicated to 

 and printed by the Royal Society. The expenses of the 

 instrumental appliances connected with this investigation 

 have been defrayed partly from a grant from the Royal 

 Society, and partly by the generosity of Dr. De La Rue, 

 to whom this Observatory owes so much, not only in the 

 matter of pecuniary aid, but by his kindly encouragement 

 and appreciation of our labours. The general result of 

 the investigation alluded to above is the comparative un- 

 suitability of any mirror for an extensive charting of the 

 heavens, and particularly as regards mirrors of short focal 

 length ; but at the same time it leaves no doubt as to 

 their capacity for the singularly accurate delineation of 

 small portions of the heavens, and for such operations as 

 those connected with stellar parallax, or the charting of 

 the moon. Preparations were made for the necessary 

 observations of the lunar eclipse of January 28 of this 

 year ; but, as was the unfortunate case with this and 

 many other Observatories, they were rendered ineffectual 

 by a clouded sky. 



The above astronomical operations made under Dr. 

 Pritchard's direction were skilfully and sedulously carried 

 out by the two Observatory assistants, Mr. Plummer and 

 Mr. Jenkins. 



NOTES. 



We learn that Dr. Guppy left England for Batavia on the 30th 

 ult. with the intention of spending some time in the examina- 

 tion of the living and upraised coral reefs of the Indian Archi- 

 pelago. Mr. John Murray has provided the necessary funds 

 for the first six months of his sojourn in that region, and has 

 directed Dr. Guppy in the first place to make as complete an 

 examination as he can of the geological structure of Christmas 

 Island. Judging from the important notes and collections made 

 by Captain Aldrich and Mr. Lister during the recent visit of 

 H.M. S. Egeria, this island would seem to be one of the oldest 

 of the upraised coral islands, and as such it is likely to prove 

 of considerable geological interest. At the last meeting of the 

 Geographical Society, Captain Wharton, the Hydrographer, read 

 a short paper on this subject. 



Apparently we have missed our chance of solving the many 

 interesting problems relating to the Antarctic regions. The 

 matter has now been taken in hand by Germany, and we may 

 be sure that she will not fail to carry out the enterprise in an 

 energetic and thoroughly scientific spirit. The expedition is being 

 organized by Dr. Neumayer, of the Hamburg Observatory. 



Mr. Jesse Collings is to be congratulated on the result of 

 his efforts to secure for the parish of West Lavington, Wiltshire, 

 the full benefit of the Dauntsey Charity, a part of which the 

 Charity Commissioners proposed to use for the establishment of 

 a High School in some other place in Wiltshire. It is now pro- 

 posed — with the approval of the Mercers' Company, the principal 

 trustees and patrons of the Charity, who have agreed to under- . 

 take a liability of ,£60,000 — not only that the children of the 

 poorer inhabitants of West Lavington shall be provided with an 

 ordinary elementary education, but that a fully-equipped Lower 

 School for technical training in horticulture and agriculture shall 

 be created for their benefit. It is intended that the latter school 

 shall be adapted to the needs of persons who cannot afford to 

 attend such institutions as those at Cirencester and Downton. 

 If the scheme is carried out, land will be provided for the more 

 thorough instruction of pupils, and classes will be formed 

 for the teaching of the various sciences and arts which especially 

 relate to agriculture. 



On July 16, Prof. W. E. Ayrton will begin, at the City and 

 Guilds of London Institute, a course of six lectures (to be de- 

 livered on Mondays, Wednesdays, and Fridays) on the con- 

 struction, testing, and use of electrical measuring instruments. 

 This course will include experimental lectures and special 

 laboratory work. The lectures will comprise the principles and 

 practice of the construction, calibration, and testing for faults of 

 ammeters, voltmeters, ohm meters, wattmeters, coulombmeters, 

 and ergmeters as used for direct and alternating current systems. 

 The students' practical work will be conducted in a laboratory 

 specially fitted with accumulators, standard instruments, &c. , 

 for electrical instrument testing ; and they will have the oppor- 

 tunity of examining and practically trying all the more important 

 electrical meters at present in ordinary use. 



An interesting Exhibition of hygiene and life-saving apparatus 

 has been opened in the Park Leopold at Ostend, The exhibits 

 are divided into the following sections : — Applications of geo- 

 logical, meteorological, and medical science to hygiene, in- 

 dustrial hygiene, maritime hygiene, domestic hygiene, hygiene 

 of infancy, publications relating to hygiene, and life-saving 

 apparatus. 



At Messrs. Stevens' Sale Rooms on Monday, the 25th ult., a 

 specimen of Papilio caumis from Assam was sold for £,\0. 

 Mr. William Watkin, of Croydon, was the purchaser. 



At the meeting of the Scientific Committee of the Royal 

 Horticultural Society on June 26, Prof. Church contributed a 

 summary of his highly interesting and important researches upon 

 the presence of aluminium in the ashes of plants. This sub- 

 stance, instead of being peculiar to the species of Lycopodium, 

 as once supposed, is found in minute traces in the ashes of very 

 many others, a circumstance not to be wondered at, considering 

 the abundant distribution of the element in many soils. It oc- 

 curs in all the species of Lycopodium examined, except those 

 which are of epiphytic habit, and which, consequently, do not 

 directly derive their food from the soil. It does not occur in 

 the allied genus Selaginella. It occurs in the ashes of some 

 tree ferns in large proportions, sometimes forming as much 

 as 20 per cent, of the ash, as in Alsophila australis, Cyathea 

 medullaris ; while from others it is all but absent. In the British 

 species of ferns little or no alumina has been found. 



At the same meeting Mr. McLachlan called attention to the 

 notion that cold winters are injurious to insects — a notion he 

 stated to be erroneous, although, no doubt, severe alternations of 

 cold, heat, drought, or moisture, were prejudicial to insect life. 

 During the present season it was noticed generally that great 

 destruction of foliage occurred from caterpillars which destroyed 

 the succulent portions of the leaf and tied the framework and 

 fragments together by a web of fine threads comparable with 



