Grace's Guide is the leading source of historical information on industry and manufacturing in Britain. This web publication contains 143,370 pages of information and 230,032 images on early companies, their products and the people who designed and built them.
Sometimes shown as John A. Maberley, a London currier
Held steam engine patent with Jabez Carter Hornblower
By 1790 Jabez Carter Hornblower had set up in business in London with financial backing from well-to-do currier John Maberly, where he designed a new steam engine based on the patented designs of Isaac Mainwaring.
1796 Hornblower and Maberly were sued by Boulton and Watt, who claimed one of Watt's patents – concerning the condenser had been infringed.  After a long trial, judgement in 1799 was in favour of Boulton and Watt and brought about the collapse of Hornblower and Maberly's business.