Insole moved to Cardiff in 1828, and by late 1829 was in partnership with Richard Biddle as Insole & Biddle, brick, timber and coal merchants.
The move and partnership were supported by family loans and inheritances.
Biddle was one of the first agents in Cardiff for Robert Thomas's Waun Wyllt "smokeless" steam coal, sent by barge down the Glamorganshire Canal from Merthyr Tydfil, and had established a customer base in Cardiff prior to partnering with Insole.
In 1830 Insole & Biddle had premises at the Wharf on the Glamorganshire Canal at Cardiff.

The Insole & Biddle day book for 1830 records a shipment of 414 tons of Waun Wyllt steam coal to London.
This consignment was later claimed to have been the largest cargo of coal ever shipped at the Glamorganshire Canal.
The shipment did not make a profit but the quality of the coal eventually made it very popular for both household and Royal Navy use.
Insole also developed markets for coal along the Severn Estuary and in Ireland.

The Insole & Biddle partnership was bankrupted in early 1831.
Insole was able to recover his financial position within a few months, and was also left a substantial inheritance that year.
From his offices in Cardiff at the mouth of the Glamorganshire Canal, he continued as agent for Waun Wyllt coal, and contracts were written to supply London-based coal merchants.
These contracts helped establish the reputation of Welsh coal in the London markets, and were the basis on which Lucy Thomas (widow of Robert) became known as "the mother of the Welsh steam coal trade".
Although Thomas has been credited with these ventures, much of the success was due to Insole.

While their assertions were not universally accepted, the Insoles claimed to have been the first to supply the London market (in 1830), the international market (Malta, in 1831), and the Royal Navy (in 1831) with South Wales steam coal.
Insole moved to Cardiff in 1828, and by late 1829 was in partnership with Richard Biddle as Insole & Biddle, brick, timber and coal merchants. The move and partnership were supported by family loans and inheritances. Biddle was one of the first agents in Cardiff for Robert Thomas's Waun Wyllt "smokeless" steam coal, sent by barge down the Glamorganshire Canal from Merthyr Tydfil, and had established a customer base in Cardiff prior to partnering with Insole. In 1830 Insole & Biddle had premises at the Wharf on the Glamorganshire Canal at Cardiff.
The Insole & Biddle day book for 1830 records a shipment of 414 tons of Waun Wyllt steam coal to London. This consignment was later claimed to have been the largest cargo of coal ever shipped at the Glamorganshire Canal. The shipment did not make a profit but the quality of the coal eventually made it very popular for both household and Royal Navy use. Insole also developed markets for coal along the Severn Estuary and in Ireland.
The Insole & Biddle partnership was bankrupted in early 1831. Insole was able to recover his financial position within a few months, and was also left a substantial inheritance that year. From his offices in Cardiff at the mouth of the Glamorganshire Canal, he continued as agent for Waun Wyllt coal, and contracts were written to supply London-based coal merchants. These contracts helped establish the reputation of Welsh coal in the London markets, and were the basis on which Lucy Thomas (widow of Robert) became known as "the mother of the Welsh steam coal trade". Although Thomas has been credited with these ventures, much of the success was due to Insole.
While their assertions were not universally accepted, the Insoles claimed to have been the first to supply the London market (in 1830), the international market (Malta, in 1831), and the Royal Navy (in 1831) with South Wales steam coal.
George Insole