Page:Passages from the Life of a Philosopher.djvu/84

 CHAPTER VI.

Statement relative to the Difference Engine, drawn up by the late Sir H. Nicolas from the Author's Papers.

following statement was drawn up by the late Sir Harris Nicolas, G.S.M. & G., from papers and documents in my possession relating to the Difference Engine. I believe every paper I possessed at all bearing on the subject was in his hands for several months.

For some time previous to 1822, Mr. Babbage had been engaged in contriving machinery for the execution of extensive arithmetical operations, and in devising mechanism by which the machine that made the calculations might also print the results.

On the 3rd of July, 1822, he published a letter to Sir Humphry Davy, President of the Royal Society, containing a statement of his views on that subject; and more particularly describing an Engine for calculating astronomical, nautical, and other Tables, by means of the "method of differences." In that letter it is stated that a small Model, consisting of six figures, and capable of working two orders of differences, had been constructed; and that it performed its work in a satisfactory manner.

The concluding paragraph of that letter is as follows:—

"Whether I shall construct a larger Engine of this kind, and bring to