Fig. 27.
Fig. 28.
[Fig. 26] shows a plain and simple design for protecting an ordinary church. The conductor in the case of churches and all other high or extensive buildings ought invariably to be made of copper rope, other metals of less conductivity, such as iron, being inadmissible, since their employment would necessitate the use of ponderous masses of metal, which would be not only unsightly, but extremely heavy, and difficult to manipulate successfully. In the accompanying engraving ([fig. 27]) lent by the Society for Promoting Christian Knowledge, is shown a somewhat more complex structure and the method of arranging the conductors thereon. In this case there is a conductor attached to each spire, leading to and connected with the metal-work of the roof and gutters. On the gable c, and the transept gables d e, there are fixed three conductors which unite in the centre of the roof, from which they are carried down to the gutters. The same arrangement is followed for the smaller gables f g h. The water-pipes and gutters being connected with the conductors, these latter are carried down the side to the earth. It need scarcely be explained how important it is that all metal ornaments on the ridges of churches, as well as other buildings, should either be connected with the general conductors or, in the case of extensive buildings, with a conductor that is carried straight to the earth, as shown in [fig. 28]. In the case of the finials so often found on Gothic structures, it is necessary to splice the conductor round the bottom of the finial, as shown in [fig. 29]. If, instead of placing terra-cotta tiles along the ridges, a cresting of fancy iron-work is fixed there, the expense of running a conductor along the ridges will be saved.
Fig. 29.
Fig. 30.
The various methods of fixing weathercocks on to the terminal rod are fully explained in another chapter. [Fig. 30] shows the best arrangement for connecting the conductor to the terminal rod on a church spire. The copper rope which forms the conductor is spliced round the terminal rod at the bottom of the finial, and as an additional security round the base of the vane rod, which in this instance also serves as the terminal rod of the lightning conductor.
There has been much controversy as to whether it is better to carry the conductor from the roof to the ground inside a building than outside the walls. As a matter of fact, it is a question of very small importance which way the conductor is carried, so long as it arrives at the ground by the shortest possible route. Benjamin Franklin, to judge from many expressions in his works, seems to have been decidedly in favour of the inside plan, which was adopted almost universally in France and on the Continent in general on the first introduction of lightning conductors. But the method was soon abandoned, owing partly to a witty saying of Voltaire, constantly quoted to this day. Speaking of the death of the unfortunate Professor Richman, of St. Petersburg, killed while experimenting with electric discharges from the clouds, Voltaire remarked, ‘There are some great lords whom one should only approach with extreme precaution: lightning is such a one.’ A mere jocular exclamation, it would have had no great force except in France, where a bon mot may cause the fall of a king and the dethronement of a dynasty. In regard to Voltaire’s pleasantry about not approaching too close to lightning, it really had in great part the effect of preventing conductors to be laid inside the houses. Even such calm philosophers and men of science as Professor Arago quote Voltaire with approval. ‘I feel inclined,’ he remarks in his ‘Meteorological Essays,’ ‘to admit that the illustrious author (Voltaire) may be right, when I remember a case that occurred in the United States.’ The case relied upon, a very curious one, was as follows, in Arago’s own words.