The decision by the Liverpool and Manchester Railway Company to hold the trials at Rainhill was due to the concern at that time of the weight of locomotives on the rails and the capabilities of their steaming capacity in different conditions.

Timothy Hackworth was by no means a rich man, his salary barely covered the upkeep of his family and home in Shildon, and his decision to construct an engine to compete in the Rainhill Trials at his own expense, was a bold decision by him. The Committee gave permission for the construction in his own time and at his own expense. However, facilities at Shildon were poor and construction was a major problem. Most of the construction was carried out by Companies Hackworth considered capable. Because of delays in delivery of parts, it could only be assembled by working night and day, and the necessary testing of the engine had to be abandoned. The locomotive "Sans Pareil" arrived at Rainhill just in time. In a series of letters to the Secretary of the Liverpool and Manchester Railway, Stephenson did his utmost to degrade "Sans Pareil", clearly demonstrating that he considered it a serious rival to his own locomotive "Rocket". Of the initial 5 entries, 3 remained in contention, "Rocket", "Sans Pareil" and "The Novelty".

The course for the event was a few miles from Liverpool, on a level piece of track one and three quarter miles long (including one-eighth of a mile at each end for gathering speed and stopping), the engines having to run along the track, pulling 3 times their weight, 10 double trips equalling one journey. Average speed was not to be less than 10 m.p.h.  After completing 10 double trips, equalling 35 miles, fuel and water to be taken on board, and the whole journey to be repeated, making a total of 70 miles covered, equal to the distance between Liverpool and Manchester. Trials commenced 6th October 1829 and were completed on 14th, the first few days given to preparation and testing. Over 10,000 people attended the trials with the proceedings being conducted in a festival atmosphere.

Entered by George and Robert Stephenson, and Henry Booth.

weight: 4 tons 5 cwts.

On the 3rd day "Rocket" made its victorious journey, completing the 70 miles in 6 hours 2 minutes, pulling the stipulated load.

Average speed varied between 13 and 16 m.p.h.

(Arcana of Science, 1830)

The winners prize was awarded to Henry Booth, and George and Robert Stephenson.

It is not a coincidence that a Stephenson locomotive proved to be the eventual winner, as he was using his experience gained on the Stockton & Darlington Railway in his design.

"... to whose excellent construction of the machinery, I was much indebted for the favourable reward of the umpires." (memoirs of Henry Booth).