REMARKS ON COMBUSTION. ]7 



The following oxides, on the other hand, are partial fup- 

 J>orters of combuftion : 



!. Red oxide of iron*. 6. Red and brown oxides of 



2. Yellow oxide of gold f. lead **. 



3 . White oxide of fil ver £. 7 . Black oxide of manganefe. 



4. Redoxideof mercury §. 8. Acidulous oxide of antimony? 



5. Arfenic acid ||* 9. White oxide of tin ? 



This lift would doubtlefs be increafed by an accurate exami- 

 nation of all the metallic oxides not included in either of thefe 

 tables* 



Thus it appears that feveral of the products of combuftion Incombuftibility 

 are capable of combining with oxigen. The incombuftibility ° w {™ towantof 

 of products, therefore, is not owing to their want of affinity for affinity for oxi- 

 oxigen, but to fome other caufe. & en * 



5. No producl of combuftion is capable of Supporting com* Nor can they 

 bullion. This is not occafioned by any want of affinity forf u PP° rt comb uf- 

 combuftible bodies; for feveral of them are capable of com- they can com- 

 bining with an additional dofe of their bafts. But by this com- bine with com- 

 bination they lofe their properties as produces, and are Convert- 

 ed into combuftibles. The procefs therefore differs eflentially 

 from combuftion. Thus fulphuric acid, a product of combuf- Inftances. This 

 tion, by combining with an additional dofe of fulphur or its combination af- 

 oxide, is converted into fulphureous acid, a fubftance which, combuftibles, aft* 

 from feveral of its properties, I conclude to be combuftible. in g. b y P art of 

 Thus alfo phofphoric acid, a product of combuftion, is capable 

 of combining with phofphorated hidrogen, and of forming 

 phofphorous acid a combuftible body. When this Iaft acid is 

 heated in contact with a fupporter, it undergoes combuftion ; 

 but it is only the additional dofe of the combuftible which burns, 

 and the whole is converted into phofphoric acid. Hence we 

 fee that it is not ^he whole bafts of thefe compounds which is 

 combuftible, but merely the additional dofe. The compounds, 

 therefore, formed by the union of a product and combuftible, 



* Fulminates with phofphorus. 



+• Forms fulminating gold. 



X Forms fulminating filver. 



§ Forms fulminating mercury* 



|| Occafions combuftion when heated with feveral combuitibieSc 



** Occafions the combuftion of fulphur. 



Vot. II*— May., 1302. C may 



