Lightning Rod Conference. Various

the co-operation of your Society by the nomination of one or more delegates to join a Committee by whom the whole question should be considered, and to whom also any written communications would be submitted.

      The Council trust that your Society may be represented by delegates; but if that course be impossible, they invite any written suggestions which you may have to offer.

      A meeting of the delegates will be called for an early date after the receipt from the Societies consulted, of the names of the gentlemen nominated by each.

      We are, Sir,

      Your obedient servants,

      G. J. Symons, }

      John W. Tripe,} Hon. Secretaries.

      In reply to this circular all the societies invited nominated delegates, and the Conference was constituted as follows:—

Meteorological Society.	C. Brooke, F.R.S., Past President.
	E. E. Dymond, F.M.S.
	G. J. Symons, F.R.S., Secretary.
Royal Institute of British Architects.	Prof. Lewis, F.S.A.
	J. Whichcord, F.S.A., Vice President.
Society of Telegraph Engineers and of Electricians.	Latimer Clark, M. Inst. C.E., Past President.
	W. H. Preece, F.R.S., M. Inst. C.E., Vice President.
Physical Society.	Prof. W. G. Adams, F.R.S., President.
	Prof. G. Carey Foster, F.R.S., Past President.

      The steps taken by the delegates will be best explained by a short narrative chiefly formed of extracts from the minute book of the Conference.

      The first meeting was held at the rooms of the Meteorological Society, on November 14th, 1878, when all the delegates were present. Mr. C. Brooke, F.R.S., was appointed President of the Conference, and Mr. G. J. Symons, F.R.S., Secretary.

      Professor W. E. Ayrton was elected a member.

      A circular, which will be found in Appendix A, was drafted for issue to manufacturers of lightning conductors. This was sent to sixty-five firms, but only eight replied, and their answers are printed verbatim in the same Appendix. An analysis of the replies forms Appendix B. Appendix C is a reply received too late for insertion in Appendix A, and after Mr. Preece had compiled Appendix B. Another reply from an American firm will be found in Appendix I, p. (192), making ten in all.

      At a subsequent meeting, the delegates from the Royal Institute of British Architects were requested to ask the Council of that body to issue a circular to their members inviting them to furnish information respecting buildings injured by lightning. This circular, together with abstracts of the replies, and a brief Introductory Summary, by Messrs. Lewis and Whichcord, will be found in Appendix D.

      Mr. Symons submitted to the meeting a mass of statistics respecting accidents by lightning which he had collected in the years 1857–59; they were referred to Professor Ayrton, and his note upon them constitutes Appendix E.

      At the meeting on August 5th, 1879, the Secretary announced the death of the President of the Conference, Mr. C. Brooke, F.R.S., a vote of condolence was passed unanimously, and ordered to be forwarded to Mrs. Brooke. The Conference then proceeded to elect a new Chairman, and it was unanimously resolved that Professor W. G. Adams, F.R.S., be requested to accept the office.

      The following circular was approved and ordered to be forwarded to a large number of the most important newspapers and periodicals throughout the United Kingdom.

      LIGHTNING CONDUCTORS.

      To the Editor of——

      Sir—

      In the summer of 1878 delegates were nominated by the following Societies, viz., the Royal Institute of British Architects, the Society of Telegraph Engineers, the Physical Society, and the Meteorological Society, for the following purpose:—

      “To consider the possibility of formulating the existing knowledge on the subject of the protection of property from damage by electricity, and the advisability of preparing and issuing a general code of rules for the erection of Lightning Conductors.”

      The delegates have held several meetings, and have already collected, firstly, from the manufacturers of Lightning Conductors, and secondly, from the Members of the Royal Institute of British Architects, a large amount of thoroughly practical information. Several of their number are also engaged in forming abstracts of the salient features of the literature of the subject.

      The Members of the Conference are, however, most anxious that their Report should be as trustworthy and as exhaustive as possible, and they have, therefore, instructed me to ask you to assist them by publishing this epitome of their proceedings, and allowing them to invite correspondence upon the points mentioned below.

      I am, Sir,

      Your obedient servant,

      G. J. SYMONS, F.R.S.,

      Secretary to the Conference.

      Lightning Rod Conference,

      30, Great George Street, S.W.

Class of Facts most Required.

       Table of Contents

      Full details of accidents by lightning, stating especially whether the building struck had a conductor or not. If there was a conductor, state its dimensions—construction—mode of attachment to building—whether its top was pointed—distance of its upper terminal from the place struck—nature and extent of the connection between the conductor and the earth, and whether the earth was dry or moist—whether the conductor was itself injured—and whether the conductor or the point struck was the most salient object in the vicinity. Information is also desired, either verbally or by sketches, as to the position of metal spouting and lead roofing relatively to the point struck, and to the conductor.

      Details of the thickest piece of metal melted by a flash of lightning are much needed.

      Unimpeachable evidence of the failure of conductors is much desired, as such failures would be extremely instructive.

      The replies were by no means as numerous as was expected: the most important will be found in Appendix I.

      At the meeting, October 27th, 1879, it was resolved “That the members of the Conference will undertake to prepare abstracts of the principal English and Foreign books upon Lightning Conductors.” This work became extremely heavy, and occupied much time, as will be seen from Appendix F, which contains abstracts of sixty separate treatises, of which 26 are from English, 17 from French, 6 from Belgian, 5 from American, and 5 from German authors, and one is from the Norwegian.

      In order to guard against omitting important works, it was resolved “That application be made to the Society of Telegraph Engineers for advance sheets of the Ronalds Catalogue.” From it, supplemented by Mr. Latimer Clark’s and other lists, the Secretary compiled Appendix G., which contains the full titles of no fewer than 704 separate works upon lightning conductors, or on subjects intimately connected therewith.

      At the same meeting it was resolved that efforts be made to obtain a set of the official instructions issued in all foreign countries. The