In the fascinating world of railways there has never been a shortage of ideas. Many come from outside the industry and some of them even have practical applications, for which I am sure we are immensely grateful. Most, though, are not really very well thought through. One of these ideas involved lighting, and my excitement was heightened when I discovered a link with a possible ancestor of mine (and possibly two of them). The idea involved free lighting. Who would turn that away?
It came to pass that one day, early in 1880, the Metropolitan Railway was induced to take an interest in the idea of free lighting. The Metropolitan Railway, being an underground railway was perhaps more interested in lighting than many other railways at that time and I would describe its attitude as mildly curious rather than hugely enthusiastic. Nevertheless, if the idea worked, it might show promise.
The idea was demonstrated in a First Class Great Western Railway carriage that ran on the through service between the home counties and Aldgate. The interior of the carriage was painted in Professor Balmain’s luminous paint; this comprised a mixture of Calcium Sulphide and a particular kind of varnish and on casual inspection looked similar to the white or cream paint normally used. However, during its passage in the open air during daylight hours, the mixture absorbed a certain amount of light energy and became phosphorescent. When the carriage entered the underground railway tunnel sections east of Paddington, its interior surfaces glowed. Reports at the time acknowledge that when it went into the tunnel, the illumination was barely perceptible but as passengers’ eyes got used to the gloom the phosphorescence appeared to become brighter and endured sufficiently long to last to the terminus (topped up by daylight in the open sections). After a while, in the gloom, it became just possible to make out other passengers in the compartment.
The circumstances around all this are obscure. Balmain died in 1877 at the age of 60 and the press at the time explained he had left the ‘secret’ of the paint to his assistant, whose name was A.J. Horne. Horne carried on working on the formula and was able to improve the recipe further. It emerged that Calcium Sulphide on its own is an imperfect phosphor and needs traces of certain other elements to achieve maximum luminosity (these being selected from Manganese, Copper or Bismuth). He established from tests that blue and violet light readily generated a white output from the paint. On the other hand red and yellow had little effect but tended to diminish output. Horne apparently succeeded in making these alterations to the formula and is found a few years later manufacturing the paint from an establishment in Bromley Road, Catford.
I have not established the detail, but it seems that A.J. Horne involved the partnership of Ihlee & Horne, of 31 Aldermanbury, in attempting to raise the profile of the paint and create a market for it. There is evidence of some success here. However the Horne involved in the partnership was a Mr William Cullen Horne (who is described as a merchant). It seems very unlikely this was a coincidence and I suppose he was a relative of A.J. Horne. The man called Ihlee was an engineer, a German who came to the UK as he didn’t like what Bismark was doing creating the nation of Germany from the previously independent states. Their loss, for he was a very good engineer. Anyway, this partnership attempted to ‘work’ the patent and part of this involved holding exhibitions and demonstrations of what the paint could do. The partnership carried out a number of roadshows around the country and sought to gain railway interest.
Ihlee & Horne saw tremendous advantages in using the paint when light was only needed for short periods; they acknowledged that the paint would hardly displace the use of all oil or gas lighting inside railway carriages, but might be useful in short tunnels (though it wouldn’t if there was no time for the eyes to adjust). It was alleged at the time of the Great Western/Metropolitan experiment that the Great Northern Railway had also volunteered to provide a carriage for demonstrating the luminous paint. I have also found later reports that the Midland entertained the idea, and the Lancashire & Yorkshire Railway, which apparently thought it had more advantage for longer tunnels.
The partnership of Ihlee & Horne was dissolved in 1884; Ihlee found another business partner and I note that many years later W.C. Horne filed a patent for a fly trap involving a phosphorescent compound, this time involving radium, which, being radioactive, kept the phosphor alight, so to speak, even when not exposed to light. The Balmain phosphor was not radioactive.
Although I do not at the moment know if luminous paint was the subject of any more trials, I can say with a degree of certainty that it was not adopted by any railway company as a means of lighting. One can perfectly well imagine why such a system would not be thought satisfactory for general lighting, and the quest anyway was for much brighter lights, achieved within a few years by electricity supplied by dynamos and batteries. Even so, it is worth pausing for a moment why it might not have been pursued as a means of emergency lighting if the paint production cost was satisfactory (originally a premium was charged [it cost £1 8s per pound weight] but the constituents were so cheap that it could have been sold at virtually the same price as ordinary paint).
As far as I know we hear no more of luminous paint for railway carriages, though it was thought useful for a number of other purposes. For an underground railway one might even have thought it went into the ‘just do it’ category, but it did not.
I now need to find out more about these Hornes and whether they are anything to do with me!