On the Decomposition and Composition of the Alkalis. 101 



inconsistencies. It is seriously to be hoped, as research has 

 developed abundant examples of anfiea't art, that those ex- 

 amples which contain what is useful, chaste, and elegant, 

 will prevail among a people not less distinguished for their 

 taste than their erudition ; and that the architect, true to the 

 genuine purpose of his art, will consider an Herculancum 

 and a Pompeii as containing stores whereby his reputation 

 may be raised on surer ground, titan on the imitation of 

 forts and towers. 



J. R. 



XVII. The Bakerian Lecture, on some new Phcenomena of 

 Chemical Changes produced try Electricity, particularly 

 the Decomposition of the fixed Alkalis, and I he Exhibition 

 of the new Substances which constitute their Bases; and 

 on the general Nature of alkaline Bodies. By Humphry 

 Davy, Esq., Sec. R. S. M.RJ.A, 



[Continued from p. IS.] 



V. On the Properties and Nature of the Basis of Soda. 



J- he basis of soda, as I have already mentioned, is a solid 

 at common temperatures. It is white, opaque, and when 

 examined under a film of naphtha has the lustre and gene- 

 ral appearance of silver. It is exceedingly malleable, and is 

 much softer than any of the common metallic substances. 

 When pressed upon by a platina blade, with a small force, 

 it spreads into thin leaves, and a globule of the -f-^ih or 7l V*h 

 of an inch in diameter is easily spread over a surface of a 

 quarter of an inch*, and this property does ' not diminish 

 when it is cooled to 32° Fahrenheit. 



It conducts electricity and heat in a similar manner to the 

 basis of potash; and small gjobulcs of it inflame bv the 

 voltaic electrical spark, and burn with bright explosions. 



Its specific gravity is less than that, of water. It swims 

 in oil of sassafras of 1*096, water being one, and slides in 



* Globules may be easily made to adhere and Conn one rvsasi bv strono- 

 pressure : so that the property of welding, which belongs to iron ?jid platina 

 at 2. white heat only, is possessed by this substance at comrnau temperatures. 



G 3 naphtha 



