August i6, 1900] 



NATURE 



379 



the sudden rattling of a large window was distinctly heard at 

 about 10 p.m., but it was unaccompanied by any sound. 

 Judging from the intensity of the disturbances at Torquay and 

 Brighton, I see no reason to doubt the connection of the 

 latter observation with the firing at Cherbourg. 



It is interesting to notice how the character of the sound 

 changed with the increasing distance from Cherbourg. At St. 

 Catherine's Point (65 miles) and Bonchurch (68 miles), both in 

 the Isle of Wight, the sound was described as exactly like that 

 of heavy guns. At Bournemouth and Muddiford in Hampshire 

 (74 miles) there was a continual rumbling noise, with occasional 

 heavier booms. At greater distances, as far as Lancing, Tor- 

 quay and Paignton, the prominent reports ceased to be audible, 

 and there was merely a deep monotonous throbbing noise, the 

 pulsations recurring with great rapidity and regularity, resem- 

 bling a very quick beating of a big drum far away, or the beats 

 of the paddles of a distant and unseen steamer. At very great 

 distances the vibrations (or some of them) do not seem to have 

 attained the requisite strength to be audible to certain observers, 

 one at Lancing (too miles) referring to a most curious throbbing 

 sensation in the air, and a dull sound like that of a distant train ; 

 while another at Brighton (104 miles) remarks that he heard or 

 felt the sound. The rattling of the window and the in- 

 audibility of the vibrations at Menheniot may perhaps be 

 accounted for in this way. Charles DXvison. 



• SUBJECTS FOR CON'^IDERA TION B Y 

 ELECTRICAL ENGINEERS. 

 'T'HE current number (July) of \.\\q Journal oi the Institution 

 -'■ of Electrical Engineers cont.ains a list of subjects suggested 

 by the Council as suitable for papers to be read at the meetings 

 or published in the Journal. The list is here reprinted, and it 

 should be the means of directing attention to many important 

 problems awaiting solution, as well as eliciting information upon 

 the present position of various branches of electrical engineering. 



1. Best methods of generating steam and steam power for 



variable loads. 



2. Comparison of double- and triple-expansion engines for 



varying load conditions. 



3. Automatic handling of fuel in power stations. 



4. The present position and applicability of gas or oil engines 



for electrical power stations. 



5. Description of plants for the utilisation of river- or tidal- 



power in the generation of electrical energy. 



6. The present position and prospects of the application of 



liquid and of powdered fuel in electrical power stations. 



7. The utilisation of blast-furnace gases or other waste products 



of manufactures in the generation of electricity. 

 8 The application of dust-destructors to the generation of 



electricity. 

 9. Electric light and power station chimney shafts ; specialities 



of their construction and equipment. 



10. Experiences with vibrations from electric light and power 



stations. 



1 1. Bearings of shaft and shafting running at high speed. 



12. Improvements in dynamos. 



13. Comparison of speed and cost of dynamo. 



14. Comparison of single and multiple central stations. 



15. The wholesale supply of electricity to towns and factories 



from centres where very large generating units are em- 

 ployed. 



16. The distribution of electrical energy from a distant generating 



station through districts served from a different source of 

 supply, or under a separate local authority. 



17. Electrical distribution by constant current, direct or 



alternating. 

 iS. Examination of relative advantages and disadvantages of 

 direct-current and alternate-current transmission. 

 Examination of relative advantages and disadvantages of 

 two-phase and three-phase transmission. 



20. Methods of controlling speed of alternating current motors. 



21. Practical methods of measurement in connection with 



polyphase distribution. 

 11. Methods for the conversion of direct current into alternate 

 current. 



23. Methods of providing for electrical supply during hours of 



small demand. 



24. Utilisation of lighting plant for other work during the hours 



of small demand. 



NO. 1607, VOL. 62] 



30. 



The electrical equipment of large blocks of ottices in a city. 

 Economy of design in the manufacture of small electric 



fittings. 

 Portable electric lamps of the "safety" type, or otherwise. 

 Enclosed arc lamps. 



Improvements in incandescence electric lamps. 

 Incandescence electric lamps with filaments other than pure 



carbon. 

 Application of electrical transmission in factories : — 



(a) Detailed description, giving sizes of motors and 



power provided. 

 {h) Comparison of separate or combined direct- and 



alternate-current methods, 

 (f) Combination of lighting and power for such 

 purposes 

 Electricity meters. 

 Description of electrical methods, or comparison of these 



with other methods, of propelling vehicles. 

 The supply of electrical energy for tramway purposes. 

 The use of electrical methods of traction on railways served 



by steam-driven locomotives. 

 The economy and design of electrical elevators. 

 The design and economy of electrically driven pumps. 

 The utilisation of electrical energy in mining. 

 The applications of electrical energy in warfare. 

 The use of electricity in the textile and other industries. 

 The application of electricity in musical instruments. 

 Electro-therapeutics. 



The establishment of public time-services by electricity. 

 Recent advances in telegraphy. 

 Applications of alternating currents in telegraphy. 

 The transmitting capacity and load factor of telegraph 



circuits. 

 Hertzian telegraphy. 

 Methods, in aerial telegraphy, of restricting signals to 



selected stations. 

 Recent improvements in telephony. 

 Descriptions of systems tending to simplify the interchange 



• of telephonic communications. 

 The talking capacity and load factor of telephone circuits. 

 The application of electricity to the generation of heat for 



domestic purposes (cooking, ventilation, heating, &c.). 

 The construction and use of electric furnaces. 

 The application of electricity to the welding or annealing 



of metals. 

 The application of electrical heating methods in chemical 



or metallurgical operations. 

 The applications of electricity in metallurgical processes. 

 The applications of electrolysis in the smelting or refining 



of metals, or in the chemical industries. 

 The electrical equipment of chemical factories. 

 Improvements in primary batteries. 

 Examination of the present position of secondary batteries 



in electrical engineering. 

 The direct generation of electrical energy from fuel. 

 The economic employment of thermo-generators. 

 Improvements in the apparatus for producing, and in the 



applications of, kathode and Rontgen rays. 

 The relative suitability and efficiency of the different 



materials available for any of the requirements of electrical 



engineering. 

 The electric strength of di-electrics. 

 Recent advance in the manufacture or use of insulating 



materials. 

 New insulating materials. 



Electrical applications of aluminium, sodium, &c. 

 The electrical uses of the rarer metals. 

 The treatment, testing, specifications, or uses of iron or 



steel, or of iron alloys, for magnetic purposes. 

 The manufacture of permanent magnets. 

 The relation of chemical composition and physical condition 



to the electrical or magnetic properties of substances, 



considered in its bearing upon electrical engineering 



practice. 

 High-resistance metals for instruments or resistance coils. 

 New resistance alloys. 

 The protection of laboratories and observatories against 



magnetic disturbances due to local causes. 

 Recent legislation in its relation to electrical undertakings. 

 The relations between electric lighting or power corporations 



and municipal authorities. 



