I lent him for exhibition numerous specimens of the unfinished portions of the Difference Engine No. 1. These I had purchased on the determination of the Government to abandon its construction in 1842.
I proposed also to lend him the Mechanical Notations of the Difference Engine, which had been made at my own expense, and were finished by myself and my eldest son, Mr. B. Herschel Babbage.
I had had several applications from foreigners[28] for some account of my system of Mechanical Notation, and great desire was frequently expressed to see the illustrations of the method itself, and of its various applications.
[28] One object of the mission of Professor Bolzani was, to take back with him to Russia such an account of the Mechanical Notation as might facilitate its teaching in the Russian Universities. I regret that it was entirely out of my power to assist him.
These, however, were so extensive that it was impossible, without very great inconvenience, to exhibit them even in my own house.
〈THE LOAN OF OTHER CALCULATING MACHINES OFFERED.〉
I therefore wrote to Mr. Gravatt to offer him the loan of the following property for the Exhibition:—
- 1. A small Calculating Machine of the simplest order for adding together any number of separate sums of money, provided the total was under 100,000 l., by Sir Samuel Morland. 1666.
- 2. A very complete and well-executed Machine for answering all questions in plane trigonometry, by Sir Samuel Morland. 1663. {155}
- 3. An original set of Napier’s bones.
- 4. A small Arithmetical Machine, by Viscount Mahon, afterwards Earl Stanhope. Without date.
- 5. A larger Machine, to add, subtract, multiply, and divide, by Viscount Mahon. 1775.
- 6. Another similar Machine, of a somewhat different construction, for the same operations, by Viscount Mahon. 1777.
- 7. A small Difference Engine, made in London, in consequence of its author having read Dr. Lardner’s article in the “Edinburgh Review” of July, 1834, No. CXX.
List of Mechanical Notations proposed to be Lent for the Exhibition.
- 1. All the drawings explaining the principles of the Mechanical Notation.
- 2. The complete Mechanical Notations of the Swedish Calculating Engine of M. Scheutz.
- These latter drawings had been made and used by my youngest son, Major Henry P. Babbage, now resident in India, in explaining the principles of the Mechanical Notation at the meeting of the British Association at Glasgow, and afterwards in London, at a meeting of the Institution of Civil Engineers.[29]
- 3. The Mechanical Notations of the Difference Engine No. 1. {156}
- These had been made at my own expense, and were finished by myself and my eldest son, Mr. B. Herschel Babbage, now resident in South Australia.
- 4. A complete set of the drawings of the Difference Engine No. 2, for calculating and printing tables, with seven orders of differences, and thirty places of figures. Finished in 1849.
- 5. A complete set of the Notations necessary for the explanation and demonstration of Difference Engine No. 2, finished in 1849.