His first model, made with toothed wheels in shafts that were turned by a crank could produce a table of squares up to five places. He contacted the British Government in 1822, pointing out the advantages of his Difference Engine and offering to construct one for government use.

At a time when government grants for science were practically unknown, the Chancellor of the Exchequer made a vague verbal agreement to underwrite the enterprise with government funds.

The proposed engine was to be much grander, with 20-place capacity and up to sixth order differences. As a number appeared in the answer column, it was to be transmitted through a set of levers and cams to a collection of steel punches, which would stamp the number on a copper plate. Mechanically, this was an enormous order when you consider that standardized parts still were practically non-existent.