SEARCHING FOE WE KNOW NOT WHAT, AND FINDING IT. 239 



of considerable heat. This was the origin of the so-called 

 ' explosive antimony.' I subsequently investigated the phe- 

 nomenon, and found that by slightly scratching a thick piece 

 of the substance, the temperature it suddenly acquired was 

 sometimes nearly as high as 700 F. 1 In a similar manner, 

 by subjecting a large number of substances in succession to 

 contact with liquefied anhydrous hydrochloric acid under 

 very great pressure, I discovered the singular circumstance 

 that by contact of a porous piece of caustic lime with that 

 liquid, contrary to expectation, the two bodies did not 

 chemically combine, and therefore that neither water nor 

 chloride of calcium was formed. 



From these various considerations and instances, it is 

 evident that the most unexpected discovery, or even a dis- 

 covery contrary to expectation, made by a scientific man, 

 is usually a result of definite search, and that the term 

 6 accidental ' is in nearly all cases not strictly applicable to 

 the discoveries made by scientific investigators. 



1 See Transactions of the Royal Society, 1857-58, and 1862. 



