Beport of the Progress of the Sciences in Prance. 3 i 



10. It is prolahle therefore that there is only one kind of 

 air, viz. pure air, which may be modified into inflammable gas, 

 and into azotic gas. 



11. Caloric enters, as the principle of the nitric acid, into the 

 combination of the nitrous gas and oxvgen. It ought therefore 

 to be one of the principles of the other acids, the oxides, alkalis, 

 and earths. This is the causlicum of Meyer. 



12. The new theory has therefore only the merit of having 

 confirmed the opinion of Jean Rev, and Hales, who had proved 

 that in combustion, and in the calcination of metals, there was 

 a comljination of a portion of air which augmented the weight 

 of the burnt bodv ; a truth to which too little attention has since 

 been paid. But it was wrong to reject the principle of inflam- 

 mai>iiity which exists in combustible bodies, as well as the ca- 

 loric v/hich is combined in the new products. The new no- 

 menclature, besides, is very imperfect. 



13. It is probable, therefore, accm-ding to tlie present notions, 

 that an acid, the sulphuric for instance, is composed, 



a. Of a base, that of sulphur. 

 /'. A portion of hydrogen. 



r. oxygen. 



d. caloric combined. 



€. water. 



The same may be said of the oxide«, earths, occ. 

 There ai-e some exceptions, hou-ever: the oxymuriatic, fluoric, 

 and iodic acids do not contain oxygen, but hydrogen. 



14. But what are the bases of sulphur, phosphorus, &;c. ? 

 Tiii> is a question in chemistry which remains to be solved. 



Chemists have wished to regard all tliese bases as simple ele- 

 mc'iiif!, or at least indecomposed, because art has not yet de- 

 composed them. But I have constantly maintained that, sup- 

 posing most of these baies had not yet been decomposed, every 

 tact seems to prove that a great number of th.eoc bases, and per- 

 haps the whole, are daily composed : they are produced like the 

 principles said to be innnediale of vegetables and animals. 



a. The fluoric acid is found in the teeth : what is it that 

 furnishes it, if it be not a new product ? 



b. Phosphorus is very abundant, in animal and vegetable sub- 

 stances, in the form of phosphoric acid. We may say the same 

 of sulphur, charcoal, &;c. What is it that furnishes them, if 

 tiiey are not new products ? 



c. Potash and soda are very abundant in vegetable and ani- 

 mal substaiK-es, and in nitre pits, the earth of which has been 

 cleansed by repeated washings from all saline substances. What 

 is it tiiat furnishes them, if tlicy arc not new products ? 



d. The earths, particularly magnesia, so abundant in the Jixi- 



viums 



