As there were many inquiries for engines that never resulted in an order or the erection of an engine, it is worth recording a list of the early inquiries received by Boulton and Watt, to show what sort of industrial enterprises felt the need of steam-power, even though from lack of capital or some other reason no engine was at the time erected.
| Date of Inquiry | Name of Inquirer | Purpose of Engine | Place of Erection | Kind of Engine |
| Oct. 18,1775 | John Collet | Polishing mill | London | Rotary |
| Oct. 22,1775 | John Bligh | Water-works | Chelsca | Reciprocating |
| -Winchester | Mine | Bakewell | " | |
| B. Wilbie | Distillery | Stratford-le-Bow | " | |
| Dec. 14,1775 | J. Scott | Colliery | Shrewsbury | " |
| Feb. 16,1776 | S. Garbett | Iron-works and colliery | Carron | " |
| July 3,1776 | J. Cross & Co. | Distillery | Bristol | " |
| July 26,1776 | Chas. Cash | Private water supply | .. | " |
| July 30,1776 | T. Williams | .. | Haverfordwest | " |
| Aug. 30,1776 | Sir. A. Hope, Bt. | .. | Newton, near Edinburgh | " |
| Oct. 28,1776 | C Howard, Engineer | Iron-works | Hawarden, Flint | " |
| Oct. 28,1776 | Stewart | Private water supply | .. | " |
| Oct. 28,1776 | S. Wyatt | Private water supply | .. | " |
| Nov. 2,1776 | Shadwell Water-works | .. | Shadwell | " |
| Nov. 2,1776 | West Ham Water-works | .. | Cornwall | " |
| Nov. 8,1776 | Engine to be erected free | Mine(Tin or Copper) | Cornwall | Reciprocating |
| Nov. 8,1776 | L. Langdale | Raising water | Holborn | " |
| Nov. 8,1776 | Proctor & Beilby | Mill | Sheffield | Rotary |
| Nov. 10,1776 | F. L. Kaller | Mine | Landshut, Silesia | Reciprocating |
| Nov. 12,1776 | Henshall | Colliery | Lawton, Cheshire | " |
| Nov. 12,1776 | Matthews | Mine | Broseley, Salop | " |
| Nov. 26,1776 | Beech | Colliery | .. | " |
| Feb. 16,1777 | Salmon | Brine Works | Hassall, Chesire | Reciprocating |
| 1Feb. 22,1777 | Chapman | Colliery | Newcastle-on-Tyne | " |
| - | Colville | " | Torryburn | " |
| Feb. 27,1777 | .. | " | Coseley | " |
| March 1,1777 | Wilson | Copper mine | Chacewater, Cornwall | " |
| March 6,1777 | Bockett & Janson | .. | Southwark | " |
| April 2,1777 | Gambrell | Carpenter's shop | Richmond, Surrey | Rotary |
| April 8,1777 | T. Wrothall | .. | Woodhouse, nr. Sheffield | " |
| April 8,1777 | T. Warden | .. | Macclesfield | " |
| April 24,1777 | G. Meason | Colliery | Edinburgh | Reciprocating |
| July 17,1777 | Richmond | Water-works | Richmond | " |
| Aug. 13,1777 | Ph. Clowes | Silk mill | Chesterfield | Rotary |
| Aug. 18,1777 | Burgess | Water-works | Borough water-works | Reciprocating |
| Nov. 30,1777 | Arkwright | Feed water wheel | Cromford | " |
| Dec. 31,1777 | Reynolds | Iron works | Ketley | " |
| 2April 16,1778 | M. Wright | .. | Hull | " |
2. Smeaton received the contract for erecting this engine, but having seen the Boulton & Watt engine at the Birmingham Navigation, surrendered the Hull engine contract to Boulton & Watt.