It was said that Angus Croll was the first to use oxide of iron for purification but that he failed to discover the revivification process later developed by Richard Laming and F.J. Evans. This was not quite true; the origins of the process for which Frank Hills held the patent went back many years before Croll's entry into the gas industry.
In the Institution of Gas Engineers' Library is a collection of letters dating from around 1816. The correspondents include a Mr. Johnson, who lived in Ireland and was later to come to England with purification process of his own, Aaron Manby the Shropshire Ironmaster who also manufactured ready made gas works and a Daniel Wilson. It emerges that Wilson had just come to London from Dublin with a purification process that he wanted to sell to the gas industry. Johnson was his friend and confidant. In Dublin they had been backed by a Major Taylor. Taylor was clearly an important man - the letters suggest he was a trustee of Dunleary harbour. It is not impossible that he was related to John Taylor who had an uncle in Ireland. The letters describe Wilson's attempts to lobby the nascent gas industry and his eventual liaison with Aaron Manby. Those between Johnson and Wilson are clearly between close friends and sometimes, in almost evangelistic tones, describe their hopes of successful careers. It is what happened to Daniel Wilson and his process which is significant.
Something of the fate of Wilson's purification process can be discovered. One echo of it can be heard in 1856 when a letter from George Holsworthy Palmer appeared in Journal of Gas Lighting. He claimed that he held an old patent by then expired, which covered the 'oxide' process by then patented by Frank Hills. In 1818, after being sacked by the Chartered Company, Palmer had gone to Macclesfield where he had set up an experimental purification plant. James Hargreaves, first Deputy Governor of the Chartered, had left in unexplained circumstances. He had then set up works in Liverpool and Macclesfield. It might therefore be speculated that Palmer had gone to Macclesfield under his patronage. Palmer's process consisted of 'a purifying machine and a small condenser'. The gas went through 'fragments of sheet iron, or any oxide of iron'. A party from London came to view the installation and reported with some derision - 'the effects of the process upon the gas was imperfect and inefficient'. Palmer's patent seems have been abandoned at this point but its importance, recognised later, was that it embodied the principle of revivification. Fifty years later Lewis Thompson, who wrote an account of this episode, said there was 'no resemblance between [it and the oxide process as] ... chalk and cheese or egg of Columbus.' Thompson was a doctor who had worked in Paris with Richard Laming. In London he had set up as a consultant testing gas purity and wrote extensively about the issues surrounding the chemistry of gas lighting
In 1817 it had been noticed that Palmer's method of purification was similar to one currently being exhibited in London by Aaron Manby of the Horsley Iron Works. It was announced that Manby was employing a chemist, Daniel Wilson, who had devised and patented the purification process. One of Wilson's purifying systems was installed at the Chartered's Brick Lane works55 where it 'proved useless' and was removed. Sadly the IGE letter collection does not record this set back which cannot have been helped by Wilson's operation for fistula. Although Johnson sympathised with him for 'setbacks', Wilson only described negotiations with 'friend Livesey' together with the useful information that Clegg had left before he was sacked and that a director has 'bolted' with £50,000 of the public's money.
In 1819 a fire devastated the sugar works of Severn, King and Company in Whitechapel. A series of complicated insurance claims subsequently came to court. It emerged that the apparatus responsible for the fire had been supplied by Aaron Manby and designed for him by Daniel. Wilson. The final decision on blame was inconclusive but some witnesses, like Philip Taylor, described Wilson's process as 'hazardous'. Was this tragedy the reason for Wilson's departure to France where he stayed for the rest of his life?
In France Wilson worked with Frederick Albert Winsor, and together they set up the first Paris gas works which Wilson managed. Manby, Wilson et Cie became a major force in French industry even owning the great Le Creusot ironworks for a while. A few years later two young chemists came to France - Lewis Thompson and Richard Laming. They sought out Wilson having heard of his reputation, met him in Paris and discussed his old purification process. Richard Laming undertook research on Wilson's process and patented it in England in 1847. He subsequently discovered that if the used iron mixture was left to stand in the open air that the iron salts were reconverted and could be used again. For reasons that have never been clear he did not include this in his English patent.
When Louis Phillipe was dethroned in 1848, Thompson and Laming returned to England. Thompson went to work for Hawes soap manufactory. Details of work there are known through a legal case concerning a woman who claimed to be Thompson's unsupported wife. Hawes have an importance in this saga, partly because the company had a long standing interest in oil gas - promoted by the Taylors. Richard Laming, returning to London, set up as a manufacturing chemist in Millwall, specialising in ammonia salts. An appeal by him against his rate assessment has left a detailed description of works and equipment in the All Saints, Poplar, Rate Assessments Register.