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might have forced an entrance into the rcc. This can't be 

 done in my pump here defcribed for want of this fecond cock, 

 which might at firft have been cafily added. 



The gage-glafs or veffel is fupported by the pillar B, which 

 is fo high, as that the eye of the operator, looking over the 

 barrel, may be on a level with the furface of the mere'' in the 

 gage-velTel ; it terminates in a deep cup W, to receive the narrow 

 bottom of this veffel, which is fixed in it with cement : the 

 pillar is fixed upon the dudl of the rec' by two fcrews which 

 pafs through the iron frame underneath, and alfo through the 

 fides of the dud, which are fo thick as to admit holes for 

 the fcrews «to be made through them, without the channel of 

 the dudt ; by which both the pillar and the dud are made 

 firm. 



If a fyphon-gage fhould be preferred to the reduced bar', this 

 pillar would fupport it, and the pipe E might be conneded 

 with its open end. I have preferred the former, becaufc in it 

 the foul, confined, or fadtitious air, which may be in the rec', 

 can never get into the tube, and make its fides and alfo the 

 mere' in it foul, preventing its motion in the tube and equi- 

 librium ; as it ever will do in time in the fyphon or com- 

 mon baf^ gage ; fo that this little barom/ always ads as well 

 as at firft. To apply a whole bar' as a gage to this pump, 



when 



