[ 415 3 
LXIX. A Letter from Mr . J. Smeaton to 
Mr . John Ellicott, F. R. S. concerning forne 
Improvements made by himfelf in the Air- 
Pump. 
S I R, 
Read April i6,"W" HAVE been informed by fome of my 
1752 ‘ X friends, that my endeavours towards 
completing the air-pump, have been mentioned with 
approbation, in papers that Mr. Short and Mr. Watfon 
have lately communicated to the Royal Society. I 
underRand likewife, that the latter of thofe gentle*- 
men has, in a very obliging manner, exprefied an in- 
clination, that I fhould lay before them a particular 
account of my improvements therein. 
I (hall always eReem it a lingular honour to be 
thought capable of producing any thing worthy the 
attention of the Royal Society ; and to be my duty 
and intereR fo to do, upon the lead; intimation of 
that kind. 
Your fuperior (kill in mechanics, together with 
the affi Ranee you have given me in making trial of 
my pump, againft three very good ones of the com- 
mon conRruction, as well as the frequent marks of 
friendfhip you have fhewn me on all oecalions, en- 
courage me to trouble you with communicating the 
following to that Society, of which you are a mem- 
ber, and who, of all others,, are the moR proper 
judges.- 
I (hall 
