various other gafious Fluids. %j9 



.^I have obferved, in feveral experiments, that fulphur frequently aflumes a yellow, 

 yellowifli, or orange colour.- We are feldom deceived in fuppofing that there is fulphur 

 in bodies which exhibit that colour. Thofe bodies which contain coal are of a black, 

 brown, or a violet colour. Azote difcovers itfelf by a green colour. Plants (etiolecs) 

 which have vegetated, defended from the air and light, are white, and contain very little 

 azote. Expofe them to thefe two agents for a few 'days, they afTume a green colour, and 

 from that time the proportion of azote in their compofition becomes much more con- 

 fiderable. When nitrate of pot^afh is fufed in a glafs retort, and the oxygen gas ig 

 feparated, it is ebfervable at the end of the operation, whilft the azote is forming, that is 

 to fay, when the oxygen has a greater affinity to hydrogen than to caloric, that the green 

 colour appears, and the feparation of the oxygen gas entirely ceafes. 



But what demands the attention of every philofopher is, that when water is expofed to 

 the fun, the light decompofes it, and feparates the oxygen in large quantities. The 

 hydrogen retains the laft particles of the oxygen ; azote is formed, aiid announces itfelf 

 by a green colour. More and more of the water is decompofed ; the oxygen (which I 

 have already fhewn to be the principle of life and irritability in organized nature) becomes 

 more fixed ; and this azote, produ(jed from the efFe£t which the fun has upon water, • 

 becomes an organized body, the conferva fontinalis, a plant which lives, grows, and per- 

 petuates its fpecies. Here are the limits at which philofophy muft ftop — to admire and 

 refpe£l the fecrets of nature, without knowing if we fhall ever be permitted to penetrate 

 them. It is certain, and I have fatisfied myfelf refpe£ling it by a great number of ex- 

 periments in which I have been engaged every fummer for the fpace of more than twelve 

 years, that the influence of the folar light is abfolutely necelTary for changing the water 

 into a plant, or organized azote. No degree of heat can fupply the place of it, and this 

 experiment alone ought to be fufficient to convince every unprejudiced reafoner that heat 

 and light arc two fubftances totally different. I am furprized that this green matter of 

 Prieflley, this fontinalis, to which I have given the name of organized azote, has not 

 engaged more of the attention of chemifts. It is the moft wonderful fubftance which 

 exifts, the mod fingular body in nature. Nothing can be more abfurd than what Prieflley 

 has faid concerning it. To reafon as he has done, is, indeed, not to reafon at all. This 

 great man, whofe name will live as long as the fciences fhall be cultivated, has made the 

 moft eminent difcoveries, I admire his talents, but I am forry to obferve, that in all his 

 produdlions he appears to be more of an experimentalift than a philofopher. Whilft with 

 one hand he unfolds to us the aftonifhing fecrets of nature; with the other he is always 

 ready to ftiut our eyes in cafe we have a defire to penetrate further than he wifnes us to fee. 

 In the difpute which he maintained with Dr. Ingenhoufz, concerning the fi^bjeft of the 

 green matter about which we are fpeaking, he has given a ftriking inftance of his difiu- 

 clination to permit the wonders of nature to be beheld, except through his ecciefiaftical 

 perfpeftive. Ingenhoufz, an enlightened chemift, having defcribed feveral experiments, 

 worthy the attention of every thinking being, relating to this fingular fubftance, adds, 



Vol. IV.— September 1800. N n ' " Water 



