Memorials of the lineage, early life, education and development of the genius of James Watt

] 74 MEMORIALS OF
" Glasgow, December 9, 1773.
" Sir, — I only returned from a survey of the Forth two days ago,
and have been so much indisposed since, that I could not consider
your subject. I am to be at Port-Glasgow to-morrow with our magis-
trates, where I hope to have the pleasure of seeing you, as I under-
stand you are to dine there with them. I refer most of what I have
to say till that time, and hope you will come provided with the neces-
sary queries, and the plan of the harbour. In the meantime I send
you the dimensions of the breast-walls, which I find I intended to be
fifteen feet high ; that is, I supposed them to be founded as low as
the ordinary spring-tides, low water ; — you will at Port-Glasgow see
the contract for their pier, which I propose for a model for yours.
The breast should be founded seven feet thick, and should, by two
intakes in the first two courses, be taken in off" the outside to six feet
thick, from which it should batter to four feet thick at tops, the
greatest part of the batter should be off the outside, thus : — [Here a
drawing is given of the section.]
" Thickness at bottom, seven feet, . . 7
Thickness at top, ....
The two searcements at bottom,
The inside bottom,
The outside do., ....
On second thoughts, as it will not much increase the expense, I believe
it will be best to give it no inside batter, but to make the top thick-
ness four feet six inches, and make the inside perpendicular, which
will strengthen it against the earth that presses it outwards. I would
build in treshes of old ships'-oak to fix the sliders for bearing off ships'
sides, as proposed in Port-Glasgow new quay ; but these particulars
and others necessary I will explain to-morrow, and furnish articles of
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