One of Croll’s other interests was a gas meter which he had patented. He set up a factory to make it just south of the Canal Bridge in the Kingsland Road, Hackney. Even this was not particularly straightforward and in 1869 Croll's report as Chairman included the news that large amounts of the company's money were missing. An event which Journal of Gas Lighting was only too happy to report. In the 1860s he was also Chairman of the Gas Engine Company.
Croll also took on the management and ownership of several gas works. In the mid-1840s he took over the Tottenham and Edmonton Gas Works. The business had a majority of Scottish shareholders - associates of Croll.
He also leased gas works in Coventry and Winchester. Most importantly he became involved with Charles Pearson, the City of London solicitor (this is a different Charles Pearson to the copperas manufacturer in the last chapter) and with him set up a 'consumer' gas works for the City of London. The background to 'consumer' works has never adequately been explained. They were a common feature of the middle part of the last century and usually involved interests who wanted a say in the management of their local gas company. The City of London's works was one of the earliest - the story is told in some detail in Everard's History of the Gas Light and Coke Company. There was some dispute at the time as to Croll's exact role. Pearson had many ideas about City infrastructure. It is through him that that the City had such an early underground transport system - and he wanted to integrate this with sewage, markets and the postal system. His plans for gas were part of this system.