A project known as "The Pit" or Artesian Well at Rushey Platt (near Swindon) was a significant, multi-year excavation characterised in the records as a high-stakes "Experiment"
The initiative was divided into two distinct mechanical phases: an initial attempt powered by horses and a later, more capital-intensive phase involving a sophisticated steam engine.
Phase I: The Horse-Powered Experiment (1816)
In 1816, the company engaged William Hawley & Co. as specialized "Pit Sinkers" to begin the deep-sinking process. The workforce operated in shifts "Day and Night" to reach depths of 45 yards of sinking and 45 yards of boring. To manage the extraction of earth and the heavy inflow of water, the company utilized a Horse Gin operated by Charles Gibbs, which required constant horse power through the night. The project was technically complex, requiring structural shaft rings called "curbs" and the oversight of the renowned geologist William Smith, who acted as the "Strata Examiner" to judge the experiment's potential for success.
This first phase ended in failure on August 10, 1816, when the contractors were "obliged to give it up" after being "driven out with Water" through a bore hole at a depth of roughly 68 yards
Phase II: The Steam Engine Installation (1819–1821)
Determined to overcome the water issues that halted the initial work, the company moved from animal power to steam technology. They purchased a condensing steam engine from Whitworth & Co. specifically for the Rushy Platt site. This phase required substantial infrastructure, including the construction of a dedicated Engine House and associated buildings by L. Ansell.
The engine was a complex piece of machinery featuring a boiler with cast-iron plates, a condensing cistern reinforced with oak, a steam gauge, and an array of copper pipes and flanges. Despite this heavy investment in mechanical pumping power and the employment of miners to sink the well further, the project did not remain a permanent fixture of the canal's operations. By 1821, the company moved to liquidate this asset, selling the steam engine to Messrs. Clowes & Co.
Costs
1. Excavation and Sinking Costs (£305 13s 8d)
The physical labour of digging the shaft was the primary expense during the 1816 experiment, paid mostly to William Hawley & Co.
2. Horse-Powered Mechanical Costs (~£192)
Before steam was introduced, the company relied on a Horse Gin to raise "water and stuff"
3. Steam Engine and Infrastructure (~£1,713)
The second phase represented a massive capital investment to replace horse power with steam pumping
4. Labor Welfare, Materials, and Expertise (~£106)
Costs for this failed experiment exceeded £2,300, though a portion was recovered in 1821 when the steam engine was sold to Messrs. Clowes & Co. for £1,500.
Source: Canal Company Ledgers & Journals
In constructing the Wilts and Berks Canal, the great difficulty was in devising means for keeping up the supply of water to the high level which branched out on every side from Swindon, and which would be lowered every time a boat passed through one of the locks.
To keep up the supply a very large body of water would have to be kept in reserve at some high level, and William Smith was consulted as to how this could best be accomplished. His first plan was to obtain the necessary supply of water by means of an artesian well to be sunk in the Kimmeridge clay at New Swindon, and under his directions a well was sunk a short distance east of the Wootton Bassett road, near to the canal, and between it and what is now known as Westcott-place.
The well was sunk to the depth of several hundred feet, and to a certain extent the anticipations of Mr Smith were realised, for, a water-bearing strata having been struck, the water rapidly filled the well to within a few feet from the top. This was disappointing, as it had been hoped that the water would flow over the top, as in the case of the other artesian wells, and, by being conveyed into the canal, would keep up the supply to the necessary level.
In the hope that the supply in the well would be constant-the presumption being that the supply was inexhaustible, only requiring more force to eject it, it was decided to erect steam-pumping machinery at what is now known as the old canal house. A powerful steam-power pump was erected but on being put to work it was found that the supply of water was so limited as to be altogether insufficient for the purpose required, it being possible to pump the well dry; and when this had been done a considerable time elapsed before it would fill up again. It was after these unsatisfactory results had been arrived at that it was resolved to construct the Coate Reservoir, and obtain the necessary supply of water from that source.
Many years afterwards an artesian well was sunk by the Great Western Railway Company about two miles distant from the one sunk by Mr Smith, in a north-east direction, with somewhat better success, and at the present time the same company are prosecuting extensive works in sinking another well mid-way between the two wells, but with what success time alone can tell.