i68 On the Compofa'iM of Azott. 



g. Experiment 3 fucceeds equally whea the earthen tube is coated e!<ternaUy with a me- 

 tallic glaze : 



10, Experiment 4 fucceeds equally when the tube is filled wiiji lime, or pounded glafs. 

 The vapours of water only without azote gas arc obtained, 



1. When water is boiled in a glafs retort, and the fteam is pafled through tubes of glaf» 

 or porcelain ; 



2. When water is boiled in an earthen retort, internally coated with a metallic glaze, 

 and the vapours are pafled through tubes of glafs or porcelain ; 



3. When water is boiled in a glafs retort filled with pounded glafs, and the vapours arc 

 pafled through the tubes of glafs or porcelain : 



GENERAL REMARKS. 



In order to obtain azote gas in confiderable quantity, the water mull be gently evapo- 

 rated by a very moderate heat, and care muft be taken not to raife it. 



It may be obferved, that in all thefe experiments without exception, that as foon as the 

 laft drops of water is evaporated, the azote gas ceafes to be produced, notwithftanding the 

 continuance of the heat. 



RESULTS OF THE EXPERIMENTS. 



Such are the fa£ls, and the fimple enumeration of experiments, independent of all fyflern* 

 explanation, and theory. And it follows, 



1. That Meflrs. Wiegleb and Goettling were right In aflirming, that water is changed 

 into azote gas by the adlion of heat ; 



2. That they were wrong in maintaining that this change takes place always, and in all 

 circumftances, provided the vapours of water be in contact with ignited bodies; 



3. That Mr. Wiegleb has not proved what he advanced, namely, that the change of 

 water, into gas is owing to caloric, and that water is the bafis of every gas whatever. 



4. That the Dutch chemifts were wrong in advancing, that the change of water into 

 ajote gas never happens in any cafe, and that the gas obtained is owing to the atmofpheric 

 air having pafled through the retorts and the tubes ; 



5. That there arc circumftances in which water is changed into azote gas, and others in 

 which it is not, and that it is eafy to reconcile the two oppofite parties. 



The change of water into azote gas by the adtion of caloric and the earths being af- 

 firmed, it remains for us to difcover the folution of this problem. 



I have obferved, as well as Ingenhoufz, Von Homboldt, and Van Mons, that the 

 earths when moiftened, have the property of abforbing the oxigen of the atmofphere at the 

 ordinary temperature. I have alfo obferved what Von Homboldt has not remarked, that 

 they abforb oxigen in lefs time, and greater quantity, when they are heated. I found by 

 other experiments, that the earths alfo take oxigen from water, but that it is neceflary for 

 this purpofe, that the temperature (hould be more elevated than that of the atmofphere. 



Clay, 



