On phlogiston. 475 



fuppofed that the muriatic acid was always generated along 

 with the nitrous. 



As no muriatic acid was obtained in my experiment, 

 when made over diftilled water, it is probable that Dr. 

 Prieftley filled his tube with pump water, containing lea 

 fait, or that the water of his hydropneumatic tub contain- 

 ed forae marine acid. 



I cannot conclude this diflertation, without acknowledg- 

 ing my obligations to Dr. Prieftley, for his polite attention 

 in {hewing me a variety of experiments, when at his houfc 

 in Northumberland, and for the inftrudtion derived from 

 reading his very valuable diflertations, on different kinds 

 of air. 



Although I do not agree with the Doctor, in the theo- 

 ry which he has adopted, yet I conceive his entrance, on 

 that branch of philofophy, denominated pneumatic che- 

 raiftry, will ever be confidered, as marking an sera in the 

 fcience. 



3 <^2 Philological 



