- +. 
Ae 
Ch Saas 
3 < 
ares 
ON WATER-PRESSURE ENGINES. 13 
ragement given to inventive genius by the Society of Arts, which continues 
with renewed energy its career of public utility under the presidency of 
Prince Albert. I am satisfied, not only from the evidence which the ma- 
chine itself offers, differing as it does entirely from any of the German en- 
gines, but from the written testimony of Mr. Smeaton, that Mr. Westgarth’s 
pressure-engine was his own invention ; and that he borrowed no part of it, 
- either in plan or in detail, from anything then or previously existing on the 
continent. His idea appears to have been taken from the single-acting, 
open-topped atmospheric engine of the period; substituting the pressure of 
a column of water for the pressure of the atmosphere. 
The liberality and goodness of heart which distinguished Mr. Smeaton, no 
less than his high talent and skill as a civil engineer, appear conspicuously 
in the correspondence alluded to, from which I have thought it requisite to 
give the following extracts :— 
«« Austhorpe, April 29, 1769. 
“J had the pleasure of seeing the first complete engine of this kind at 
work in the summer of 1765, for draining or unwatering a lead mine belong- 
ing to Sir Walter Blacket, at Coldcleugh in the county of Northumberland ; 
since which time that machine has been shown to all those who had the 
curiosity to see it. Mr. Westgarth has now erected four others in the dif- 
ferent mines of that neighbourhood, one of which I have seen, and all 
attended with equal success.” 
In a subsequent letter Mr. Smeaton says,— 
«Mr. Westgarth was induced to think of applying for a patent for the 
exclusive privilege of using this invention, but previous thereto he was pleased 
to advise with me concerning it, being at that time frequently in these parts 
of the country as an agent of Greenwich Hospital. 
“Much as I admired the ingenuity of Mr. Westgarth’s invention, I dis- 
suaded him from the thoughts of a patent, as it would take a length of time 
to be sufficiently known, and the number of cases in which it could be pro- 
perly applied were not sufficient to afford such a number of premiums as 
_ might defray the expense of a patent, with a prospect of advantage to him- 
self and family. 
“J therefore recommended it to him, as the Society for the Encourage- 
ment of Arts, Manufactures and Commerce were, by handsome premiums 
and bounties, encouragers of all useful inventions and improvements, to com- 
municate his invention to them, that it might be made public, in confidence 
_ that he would obtain a bounty for the same of such value as to the Society 
should seem meet; and in consequence hereof I gave hima representation of 
the utility of his invention, with which in the year 1769 he applied to the 
said Society, and obtained a bounty upon condition he delivered to the 
Society a working model and a draught, showing the construction of the 
engine; but as the death of Mr. Westgarth, which happened not long after, 
prevented the usefulness of the machine from being so successfully spread, 
as it doubtless otherwise would have been, and as some of the most essential 
parts of the machine cannot be seen in the model without its being taken to 
_ pieces, and the drawing not being accompanied with any literal explanation, 
nor the details of it sufficiently made out, at the request of the Society I 
have now supplied these defects, that it may be published in such a manner 
that the utility of it may be seen, and the means of making and applying it 
_ be explained.” 
Tt appears that on seeing Mr. Westgarth’s engine, Mr. Smeaton suggested 
to him that if the engine instead of the great lever or balance-beam were 
made to work with a wheel, and instead of the long spear going down the 
