He said to Murdock, "it is a great thing to know what to do without.

We must have a book of blots--things to be scratched out." One of the most interesting schemes of Watt towards the end of his life was the contrivance of a sculpture-making machine; and he proceeded so far with it as to to able to present copies of busts to his friends as "the productions of a young artist just entering his eighty-third year." The machine, however, remained unfinished at his death, and the remarkable fact is that it was Watt's only unfinished work.
The principle of the machine was to carry a guide-point at one side over the bust or alto-relievo to be copied, and at the other side to carry a corresponding cutting-tool or drill over the alabaster, ivory, jet, or plaster of Paris to be executed.

The machine worked, as it were, with two hands, the one feeling the pattern, the other cutting the material into the required form.

Many new alterations were necessary for carrying out this ingenious apparatus, and Murdock was always at hand to give his old friend and master his best assistance.
We have seen many original letters from Watt to Murdock, asking for counsel and help.

In one of these, written in 1808, Watt says: "I have revived an idea which, if it answers, will supersede the frame and upright spindle of the reducing machine, but more of this when we meet.
Meanwhile it will be proper to adhere to the frame, etc., at present, until we see how the other alterations answer." In another he says: "I have done a Cicero without any plaits--the different segments meeting exactly.