Dr. Hutton, in his Life of Simpson,
prefixed to the _Select Exercises_, 1792, "that this reference
to him gave occasion to his turning his thoughts more seriously
to this subject, so as to form the design of composing a regular
treatise upon it: for his family have often informed me that he
laboured hard upon this work for some time before his death, and
was very anxious to have completed it, frequently remarking to
them that this work, when published, would procure him more
credit than any of his former publications. But he lived not to
put the finishing hand to it. Whatever he wrote upon this
subject probably fell, together with all his other remaining
papers, into the hands of Major Henry Watson, of the Engineers,
in the service of the India Company, being in all a large chest
full of papers. This gentleman had been a pupil of Mr.
Simpson's, and had lodged in his house. After Mr. Simpson's
death Mr. Watson prevailed upon the widow to let him have the
papers, promising either to give her a sum of money for them, or
else to print and publish them for her benefit. But nothing of
the kind was ever done; this gentleman always declaring, when
urged on this point by myself and others, that no use could be
made of any of the papers, owing to the very imperfect state in
which he said they were left. _And yet he persisted in his
refusal to give them up again._"

In 1780 Colonel Watson was recalled to India, and took out with him one
of the most remarkable English mathematicians of that day, Reuben
Burrow. This gentleman had been assistant to Dr. Maskelyne at the Royal
Observatory; and to his care was, in fact, committed the celebrated
Schehallien experiments and observations. He died in India, and, I
believe, all his papers which reached England, as well as several of his
letters, are in my possession. This, however, is no further of
consequence in the present matter, than to give authority to a remark I
am about to quote from one of his letters to his most intimate friend,
Isaac Dalby. In this he says:--"Colonel Watson has out here a work of
Simpson's on bridges, very _complete_ and _original_."

It was no doubt by his dread of the sleepless watch of Hutton, that so
unscrupulous a person as Colonel Watson is proved to be, was deterred
from publishing Simpson's work as his own.

The desideratum here is, of course, to find what became of