Chap. 31.] SILYER, 111 



CHAP. 30. THE MARVELLOUS OPERATIONS OF NATURE IN SOLDERING 



METALLIC SUBSTANCES, AND BRINGING THEM TO A STATE OE 

 PERFECTION. 



"While speaking on this subject, it will be as well to annex 

 the remaining particulars, that our admiration may here be 

 drawn to all the marvels presented by ITature in connection 

 therewith. The proper solder for gold is that above described ; 

 for iron, potter's clay ; for copper, when in masses, cadmia,^® 

 and in sheets, alum ; for lead and marble, resin. Lead is also 

 united by the aid of white lead j*® white lead with white lead, 

 by the agency of oil ; stannum, with copper file-dust ; and 

 silver, with stannum." 



For smelting copper and iron, pine-wood is the best, Egypt- 

 ian papyrus being also very good for the purpose. Gold is 

 melted most easily with a fire made of chaff. ^^ Limestone 

 and Thracian stone^^ are ignited by the agency of water, this 

 last being extinguished by the application of oil. Fire, how- 

 ever, is extinguished most readily by the application of vinegar, 

 viscus,^ and unboiled eggs. Earth will under no circumstance 

 ignite. When charcoal has been once quenched, and then again 

 ignited, it gives out a greater heat than before. 



CHAP. 31. (6.) SILVER. 



After stating these facts, we come to speak of silver ore, 

 the next- folly of mankind. Silver is never found but in 

 shafts sunk deep in the ground, there being no indications to 

 raise hopes of its existence, no shining sparkles, as in the case 

 of gold. The earth in which it is found is sometimes red, some- 

 times of an ashy hue. It is impossible, too, to melt^ it, except 



^5 As to the " cadmia " of Pliny, see B. xxsiv. c. 22. 



^^ *' Plumbum album." Tin, most probably. See B. xxxiv. cc. 47, 4S, 

 49. Also Beckmann's Hist. luv., Vol. II. p. 219. Bohu's Edition. 



s7 Of doubtful identity. See B. xxxiv. c. 48. 



^^ See Chapter 19 of this Book. 



23 "Thracius lapis." This stone, which is mentioned also by Nicander, 

 Galen, Simplicius, and Dioscorides, has not been identified. Holland has 

 the following Note on this passage: " Which some take for pit-cole, or sea- 

 cole rather, such as commeth from Newcastle by sea ; or rather, a kind of 

 jeat (jet)." In either case, he is probably wide of the mark, neither coal 

 nor jet igniting on the application of water. 



^ Or mistletoe, ~ In due succession to gold. 



3 See B. xxxiv. cc. 47, 53. 



