April I, 1886] 



NA TURE 



515 



which an examination is held. In regard to- silk manu- 

 facture, Mr. Magnus, in deploring the want of attention 

 given in this country to technical instruction in connec- 

 tion with this important industry, points out the great 

 improvement which has taken place in the silk trade of 

 Crefcld as a result of the establishment of the Weaving 

 and Dyeing School at that place. 



Examinations were held for the first time, in 1885, in 

 boot and shoe manufacture and in framework knitting, at 

 which a mmiber of students from the new Technical 

 School at Leicester presented themselves. 



It is satisfactory to observe that great attention con- 

 tinues to be paid to making the examinations of such a 

 character as to prevent students possessed only of mere 

 book-knowledge from passing. Practical examinations 

 were held in weaving and p.^ttcrn designing, in metal- 

 plate work, in mine surveying, and, for the first time, in 

 carpentry and joinery. In all these subjects (except mine 

 surveying), candidates have to send in specimens of work 

 duly certified as having been executed by themselves. 



The examinations were held in 167 towns in Great 

 Britain and Ireland, Manchester heading the list of pro- 

 vincial towns so far as regards the number of its success- 

 ful candidates. The Polytechnic Institution, London, 

 was equally successful, and next in order came Bradford, 

 Leeds, Bolton, and Huddersfietd. 



With regard to the prospects of the examinations in 

 May of this year, it appears from returns furnished in 

 November last that 6396 persons were receiving instruc- 

 tion in the registered classes of the Institute, as against 

 5874 in the previous year ; and it may therefore be 

 expected that a considerably increased number will pre- 

 sent themselves this year. 



It must b3 gratifying to the Institute to have received 

 an application, recently noticed in these columns, from 

 the Board of Technical Education in New South VVales, 

 to extend the examinations to that colony, and we are 

 glad to observe that the Council of the Institute, believing 

 that whatever tends to unite more closely the colonies 

 with the mother country is calculated to improve their 

 mutual trade and commerce, recommend that the appli- 

 cation should be acceded to. 



The annual meeting of the Governors was held yester- 

 day, under the presidency of Lord Selborne, who delivered 

 an address on the work of the Institute during the past 

 year. 



EXHIBITION OF BAROMETERS 



THE Royal Meteorological Society held its seventh 

 annual Exhibition of Instruments on March 16 and 

 17, in the Library of the Institution of Civil Engineers, 

 25, Great George Street, Westminster. The Exhibition 

 was devoted entirely to barometers, with the exception of 

 a few new instruments which have been brought out 

 during the past year. A very valuable collection of dif- 

 ferent forms of barometer was brought together, and in 

 those cases where it was not possible to obtain a speci- 

 men of the instrument a photograph or illustration of it 

 was shown. The Exhibition therefore practically in- 

 cluded almost every known form of barometer. 



The instruments were classified under the following 

 headings : — Mercurial Barometers : Adjustable Cistern, 

 Closed Cistern, Siphons ; Barographs; Aneroids; Metallic 

 and other forms of Barometer. There were altogether 78 

 barometers, 9 new instruments, and 33 drawings, photo- 

 graphs, &c., making 120 exhibits. 



Some very fine specimens of standard barometer on the 

 Fortin principle were exhibited — Mr. P. Adie showing 

 one with a glass plunger to raise the mercury in the 

 cistern, Mr. Casella showing another with the scale figured 

 to tenths of an inch, and Messrs. Negretti and Zambra 

 showing a third with cistern and tubular casing square 

 in section. By the side of these were placed a port- 



able barometer, with ivory float, about 100 years old, and 

 a standard barometer, by Barrow, the pattern used by 

 the members of the British Meteorological Society about 

 1S50-60. Messrs. Negretti and Zambra exhibited a self- 

 compensating barometer with a double rack moved by 

 one pinion, so that, when adjusting the vernier in one 

 position, the second rack moves in the opposite direction, 

 carrying along with it a plunger, which is the exact size 

 of the internal diameter of the tube. This firm also 

 showed a standard barometer with electrical adjustment, 

 and a new standard barometer with overflow cistern 

 adjustment. Some interesting specimens of mountain 

 barometers were exhibited, including one originally used 

 by the North American Boundary Commission in 1857, 

 which since its return has been employed by the Kew 

 Committee on the inter-comparison of the various standard 

 barometers of this country. 



Among the closed cistern barometers was the large 

 cistern one made for the Meteorological Society of 

 London in 1S37 by Mr. R. C. Woods. The proportion 

 of the calibre of the tube to that of the cistern is as i : 50, 

 a proportion which was considered sufficient to obviate 

 the necessity for applying capacity corrections. The 

 tube and cistern originally held 70 lbs. of mercury ! The 

 next instrument to this was the Kew barometer, first 

 designed in 1S53, in which the cistern is closed and the 

 scale contracted so as to obviate the necessity of correct- 

 tion for capacity. Specimens were exhibited of the marine 

 barometer, as supplied to Her Majesty's ships previous to 

 1854 ; the Kew marine barometer, as adopted by the 

 Admiralty ; the gun barometer, with the glass tube 

 packed with india-rubber to check the vibration caused 

 by firing ; and the coast barometer. The Meteorological 

 Office showed patterns of barometers as used in France, 

 Holland, and Russia. Two specimens of long-range 

 barometer were exhibited, viz. Morland's diagonal, by 

 Messrs. Negretti and Zambra, in which the top part of 

 the tube is inclined more or less from the perpendicular 

 to give an enlarged scale-reading ; and Hicks's spiral 

 tube, which gives a range of 8 inches for I inch variation 

 of atmospheric pressure. 



Among the siphon barometers were two very old 

 forms, viz. Hooke's double barometer and a Dutch baro- 

 meter, by Reballio, combining siphon and long-range 

 barometer, thermometer, and hygrometer. An interest- 

 ing relic was the mounting of the travelling-barometer 

 formerly belonging to, and used by, De Luc. The siphons 

 included Gay Lussac's, Bunten's, Jones's, Adie's,Dollond's, 

 Bogen's, and Wild's forms of barometer ; also a siphon 

 designed by Capt. J. B. Basevi, R.E., and used by him 

 in the high table-lands of Tibet, in connection with the 

 operations of the Great Indian Trigonometrical Survey ; 

 Stanley's barometer, with " rising and falling " index ; 

 and Guthrie's sensitive barometer, which has a flat hori- 

 zontal spiral in which is a bubble of air for indicating the 

 variations of atmospheric pressure, the motion of the 

 bubble being four and a half times that of the true baro- 

 metric variation. 



A specimen of Milne's barograph was shown by the 

 Meteorological Office, while Messrs Negretti and Zambra 

 exhibited their improved form of the same instrument in 

 which the paper is carried on a cylinder. MM. Redier, 

 of Paris, sent two forms (large and small) of their baro- 

 graph, which works so satisfactorily ; and MM. Richard 

 Freres,of Paris, in addition to sending a self-recording mer- 

 curial barometer, exhibited several specimens of their self- 

 recording aneroid, which is becoming so popular in this 

 country. This instrument consists of a series of eight 

 vacuum-boxes, by which the effects of the atmospheric 

 pressure are increased and transmitted by a system of levers 

 to an arm carrying a pen. The pen, of a special form, con- 

 tains an ink mixed with glycerine, and marks the curve of 

 atmospheric pressure on the paper round the cylinder, 

 which revolves once in seven davs. This firm also showed 



