April 27, i888.] 



SCIENTIFIC NEWS. 



407 



zinc dust and substances holding the component parts of 

 water in a chemical combination, so that, when the cart- 

 ridges are subjected to heat in a suitable apparatus, the 

 oxygen of the water will combine with the zinc and form 

 oxide of zinc, and the hydrogen will be liberated and re- 

 ceived and retained in a suitable receptacle. 



Damp Detector. — Mr. F. W. Beck, London-road, East 

 Grinstead, has patented an hygrometer. The apparatus 

 consists of an arrangement by which the fibre which 

 grows upon the seeds of a plant called Erodiuin gruinum 

 (a kind of " Cranebill ") is made to show with much nicety 

 the presence of dampness in any place. The lower end 

 of this fibre is fixed in the centre of a case containing a 

 dial-plate, on which is drawn a flat spiral of three turns 

 and divided into sections marked o to 29. The free point 

 of the fibre follows this spiral line, expanding or con- 

 tracting according to the extent of the adjacent dampness. 

 This coiling and uncoiling takes place when the detector 

 is placed in atmospheres of different humidity, and 

 wherever the point of the fibre rests the figures indicated 

 show as many degrees of dampness between the begin- 

 ning of the inner line marked o, signifying complete dry- 

 ness, and the end of the outer line marked 29, signifying 

 absolute moisture in the air. 



Submarine Vessel. — Messrs W. C. Storey and G. 

 Poore, London, have patented a submarine vessel. In 

 some submarine vessels there is a chamber furnished 

 with ingress and egress doors for a diver to pass through 

 from the interior to the exterior of the vessel. For this 

 purpose the diver enters the chamber when it is empty, 

 and after closing the ingress door, the chamber is filled 

 with water. The diver then opens the egress door, and 

 passes to the exterior of the vessel. The admission of 

 water alters the buoyancy of the vessel, and consequently 

 its depth of immersion, thereby rendering the operations 

 of a diver difficult to perform. The object of this inven- 

 tion is to overcome these disadvantages. To this end a 

 pump is employed so constructed and operated that it 

 discharges water overboard from the ballast tanks of the 

 submarine vessel at the same rate as it is admitted to the 

 diver's chamber. By this means the weight and buoy- 

 ancy of the vessel remain unaltered, and its depth of 

 immersion is kept constant. 



Safety Pin. — Mr. G. W. Herbert, of Birmingham, and 

 Mr. S. Guinery, of Epsom, have patented a safety pin. 

 It is constructed as follows : — At the outer end of the 

 ordinary protecting arm of the safety pin is provided a 

 sheet-metal shield, having at each side an opening through 

 which the end of the pointed arm can pass. The lower 

 part of the shield forms a loop, in which the pointed end 

 lies when the pin is closed. The end of the wire arm, after 

 passing round the end of the shield inside turns upwards 

 between the two side openings, thus forming a central 

 partition, between which and the shield there is room for 

 the end of the pointed arm. In closing the safety-pin, the 

 end of the pointed arm is passed into the shield through 

 one of the side openings, and is prevented from being 

 pushed straight out through the other side opening by 

 the central partition ; but when the pointed end has 

 sprung downwards into the lower part of the loop, 

 it can be passed out and disengaged through either side 

 of the pin. 



TECHNICAL EDUCATION. 



Technical Scholarships.— At the last meeting of the 

 London School Board a letter was read from the Cloth 

 Workers' Company, in which it was stated that the Company 

 proposed to establish five technical scholarships, to be com- 

 peted for by boys from any public elementary school in the 

 metropolitan area under 14 years of age who should have 

 reached the seventh standard. Of these scholarships /20 

 was tenable for the first year at the Finsbury Technical Col- 

 lege, and a similar amount was tenable lor the second year 

 at the same institution ; ^30 was tenable in the third year at 

 either the Finsbury College or the Central Institute of the 

 City and Guilds Institute ; and in the fourth and fifth years 

 similar sums were tenable at the latter institution. The 

 letter added that one scholarship would come in course of 

 award annually until the whole number were in tenure, and 

 requested that arrangements might be made as soon as 

 possible for the award of the first scholarship, which would 

 include a free course of instruction at the Finsbury Techni- 

 cal College and the Central Institution of the City and 

 Guilds Institute. 



Proposed Technical Institute in Chelsea and Pim- 

 Lico.--The Chelsea Library Commissioners have invited the 

 Vestries of St. George's and Fulham to assist in erecting a 

 technical institute on a freehold site generously offered by 

 Earl Cadogan. At the last meeting of the St. George's 

 Vestry a Committee was appointed to confer with the Charity 

 Commissioners on this matter. 



•^J»i^^P^<5f-^ . 



ANNOUNCEMENTS. 



People's Lectures.— The last lecture of the final course 

 for the present session was given at Walthamstow last week 

 by Mr. V. B. Lewes, v/hen the chair was taken by Mr. E. 

 North Buxton. The subject of the course, " The Atmosphere 

 in Relation to Health," which was admirably illustrated by 

 experiments on a large scale, proved exceedingly attractive, 

 and the Town-hall was densely crowded each night. The 

 same course was given in the Stratford Town-hall last month 

 to audiences of 1,200 to 1,500 people. Large numbers were 

 turned away from the doors at the second and third lectures. 

 The success of these courses has been so marked that steps 

 have been taken towards securing at both places a full course 

 of ten lectures and classes next winter in connexion with the 

 Society for the Extension of University Teaching, and already 

 a sufficient number of names have been received of persons 

 willing to take tickets to render the success of the centres 

 certain. The remarkably large audiences which have attended 

 the various courses of People's Lectures prove that a real 

 educational need has been touched, and it is to be hoped 

 that the Gilchrist Trustees, who have given such generous 

 support to this movement, will find it possible to carry on 

 the work on a still larger scale next winter. 



Melbourne Centennial Exhibition. — The Fine Art Com- 

 mittee of the Royal Commission for the Melbourne Exhibi- 

 tion will be prepared to inspect drawings proposed for the 

 exhibition on Wednesday, May 2. Such drawings must be 

 sent to the Pantechnicon, iVIotcomb-street, S.W., between the 

 houra of 10 and 6 on May i, accompanied in each case by a 

 note giving titles, prices, and artist's full name and address ; 

 and the same particulars must appear at the back of each 

 work. All drawings must be framed and glazed. The ex- 

 pense of packing and conveying accepted works to Melbourne 

 and back, if unsold, will be defrayed by the Royal Commis- 

 sion. Every care will be taken of the drawings, but the 

 Royal Commission cannot, under any circumstances, under- 

 take to he responsible for loss or damage. Drawings by 

 members of the Royal Academy, the Royal Society of Painters 

 in Water Colours, the Royal Institute of Painters in Water 

 Colours, and the Society of British Artists, will be accepted 

 without inspection. 



The Commission Internationale du Metre. — Mr. George 

 Matthey, F.R.S., of the firm of Johnson, Matthey, and Co., 

 has received from M. Flourens, the French Minister of 



