420 



NATURE 



[September 28, 1911 



the alternative Asterophyllites, which usually 

 ends itself to Continental workers. The point 

 in. a appear to he a small one, but any change of 

 importance as regards nomenclature at the hands of 

 the leading authority on the systematic study of 

 Carboniferous plants in this country is worthy of note. 

 Anion;; the plants more fully described, on which new 

 contributions to our knowledge are offered, we would 

 particularly direct attention to the stems and cones of 

 Calamites paleaceus, Stur., Selaginellites Gutbieri 

 (Gcepp.), Pinakodendron ohmanni, Weiss, and Spheno- 

 phyllum majus (Bronn). The memoir concludes with 

 a discussion on the age and horizon of the Hainaut 

 basin. 



In conclusion, the Belgian pakeohotnnists may be 

 congratulated on this noteworthy addition to the 

 literature on their fossil floras, and on their good 

 fortune in having secured such an authority as Dr. 

 Kidston to fulfil the task. 



To the author we would add our congratulations 

 on the successful completion ot a volume which must 

 have occupied his attention for many years past, and 

 will always rank high in the annals of systematic 

 palseobotany. We may also express the pious hope- 

 that son).' da) our own British Carboniferous flora may 

 receive an equally adequate treatment at his hands. 



E. A. N. A. 



THE ELECTRICAL EXHIBITION AT 

 OLYMP1A. 



THE important lesson to be learned from the Elec- 

 -*■ trical Exhibition at Olympia is that rapid strides 

 are being made towards a period of hygiene in our 

 daily lives for which electricity will be wholly re- 

 sponsible. During the last six years a large number 

 ot electricit) supply companies and corporation elec- 

 tricity departments have reduced their price for energy 

 for heating, cooking, and similar domestic purposes 

 to about one penny per unit, and manufacturers of 

 cooking and heating apparatus have been developing 

 this side of the industry with commendable rapidity. 

 The large percentage of firms exhibiting and demon- 

 si rating domestic appliances, together with the com- 

 parative absence ol heavy electrical machinery at 

 Olympia, sufficiently indicates the aspect of elec- 

 trical supply which is receiving the most attention. 

 A factor in this important problem has been the 

 development of cheaper wiring systems, a develop- 

 ment purposely directed to securing the smaller con- 

 sumer. In this direction also is to be noted the 

 tendency towards the production of smaller and cheaper 

 meters, cheaper service boxes, main switches, and 

 other auxiliary apparatus. 



Another factor which is helping to render the 

 installation of electric light more economical, and 

 therefore further within the reach of the smaller user, 

 is that, owing to small devices, such as lamp-holders, 

 switches and fuses being manufactured in large 

 quantities, and practically to a few standard designs, 

 the cost of these is now far less than it was a few 

 tgo. This brings us to mention what is per- 

 haps the most remarkable sign of the development of 

 the electrical industry to the ordinary thoughtful 

 observer outside the industry iiself. Fiftv years ago, 

 or even loss, electricity, except in so far as its appli- 

 cations to telegraphy were concerned, was practically 

 ibstract science, fascinating no doubt on account 

 11 iis potential developments, but scarcely a serious 

 in engineering. Now, however, not onlv is 

 electricity a most important agent in practically all 

 branches of engineerine, but the manufacture of elec- 



trical plant and apparatus has assumed the propor- 

 tions of a great industry. It is the commercial aspect 

 of this industry which is so very clearly brought home 

 to the visitor at the exhibition, especially in the case 

 of those smaller pieces of electrical apparatus which 

 form the bulk of the exhibits. The manufacture and 

 sale of these has developed into an enormous i 

 and one can see that the exhibitors at Olympia an- not 

 only engineers and electricians, but are business men 

 and traders, in the widest acceptance of these terms. 



To return to the actual exhibits. It will be noticed 

 that one of the most outstanding features of the ex- 

 hibition is the improvement in electric lamps. Onh 

 a few years ago the metal filament lamp was an 

 object of scientific interest, the difficulties of even 

 squirting the filament not then having been over- 

 come to the extent of producing a lamp with any 

 considerable degree of capability to withstand rough 

 usage. Some of the metal filament lamps shown now 

 are exhibited under conditions designed to illustrate 

 that they are as strong mechanically as the carbon 

 filament lamps which they are rapidly superseding. 

 Several manufacturers are now making filaments of 

 drawn tungsten, and the clou of the exhibition, from 

 the electrical engineer's point of view, is a 16-c.p. 220- 

 volt Osram lamp, which has a filament only o'oi5 mm. 

 diameter, and yet possesses wonderful mechanical 

 strength. Other lamps are shown, fitted on two 

 model tramcars, which are allowed to run down in- 

 clines and collide with one another. Before th 

 moment of impact, the lamps are purposely switched 

 off, as it is when the filaments are cold that the; 

 more brittle; yet the lamps withstand this roug 

 usage without any damage, and are again lighted 

 automatically as they are propelled up the inclines 

 to enable the operation to be repeated. 



The standardisation to which we have alluded applies 

 to a considerable extent to lamp shades and reflectors, 

 and concurrently with this the old haphazard way of 

 installing lighting systems is giving way to more 

 precise methods. Shades and reflectors of the Holo- 

 phane type, designed to effect even distribution 

 light, are exhibited as stock articles by several firms, 

 and much information is available at the exhibition 

 in this hitherto little considered detail of electric light- 

 ing. The most careful arts of the glassworkei 

 now employed to give effect to the investigations of 

 the student of optics in the production of diffusing 

 globes and reflectors which, by conservation and re- 

 direction of the rays of light, prevent waste and g 

 maximum effect in any desired direction. 



The adaptability of electricity to artistic fittings is 

 also well demonstrated in an exceedingly fine show 

 of models to suit almost every style of architectui 

 the English and Dutch schools. There is also a dis- 

 play of some very daintv French crystal pendants, 

 together with reproductions of the genuine old Dutch 

 lighting fittings of the sixteenth and seventeenth 

 centuries. 



A now development that may be mentioned is in 

 connection with the mercury-vapour lamp. \ "ligB 

 transforming reflector" is being introduced, made o\ | 

 material which becomes fluorescent under the action 

 of the light from the lamp, and increases the number 

 of red rays; although this has not actually solved the 

 problem of converting the light from the mercurfl 

 vapour lamp into a pure white light, it is at any rate 

 a step in the desired direction. 



The visitor who proposes onlv to spend a short time 

 ,11 the exhibition in which to form an idea ol thl 

 numerous domestic applications of electricity to which 

 we have alluded will find a large number of these 

 concentrated in the " Electric Home." This i- I 



NO. 2187, VOT,. 87] 



