6 JOSEPH PRIESTLEY i 



and, here, happening to live next door to a public 

 brewery, as he says, 



"I, at first, amused myself with making experiments on 

 the fixed air which I found ready-made in the process of 

 fermentation. When I removed from that liouse I was 

 under the necessity of making fixed air for myself; and 

 one experiment leading to another, as I have distinctly 

 and faithfully noted in my various publications on the sub- 

 ject, I by degrees contrived a convenient apparatus for the 

 purpose, but of the cheapest kind. 



" When I began these experiments I knew very little of 

 chemistry, and had, in a manner, no idea on the subject be- 

 fore I attended a course of chemical lectures, delivered in 

 the Academy at Warrington, by Dr. Turner of Liverpool. 

 But I have often thought that, upon the whole, this circum- 

 stance was no disadvantage to me ; as, in this situation, I 

 was led to devise an apparatus and processes of my own, 

 adapted to my peculiar views ; whereas, if I had been pre- 

 viously accustomed to the usual chemical processes, I 

 should not have so easily thought of any other, and without 

 new modes of operation, I should hardly have discovered 

 anything materially new."* 



The first outcome of Priestley's chemical work, 

 publislied in 1772, was of a very practical charac- 

 ter. He discovered the way of impregnating 

 water witli an excess of " fixed air," or carbonic 

 acid, and tliereby producing what we now know 

 as " soda water " — a service to naturally, and 

 still more to artificially, thirsty souls, which those 

 whose parched throats and hot heads are cooled 

 by morning draughts of that beverage, cannot 

 too gratefully acknowledge. Tn the same year, 



♦ Autohiography. ^'ij KM), 101. 



