3<54 Sulphurteus yield CcmhlnatlcHi, 



fevcral years pad, in confequence of my refcarches into the animal analyfis. They woulJ 

 be fufiicient to change the afpe£t of phyfiology and medicine ; but I have been careful not 

 to publilh them until well matured and proved by cxj crience, left 1 (hould otherwife em- 

 barrafs two fciences at once. I wifli to rifle nothing of this kind, but proceed gently, and 

 hope to arrive at folid conclufions in the couife of time. I am carneftly defirous of feeing 

 the work of Mr. Hildebrandt, as well as that of M. Humboldt. Notwithftanding the fpecd 

 they appear to fhew in their chemical explanations of vegetable and animal life, I know 

 not why I am pcrfuaded that they are lefs advanced than we in the analyfis and true in- 

 timate knowledge of the materials of thefe two kingdoms. I very much commend their 

 zeal, and admire their bold advances; but they cannot blame our well-grounded caution and 

 prudent flownefs. It is admirable to proceed with expedition, and make great advances iti- 

 the paths of nature ; but it is fliil better to obferve well, to fee clearly, and to communi- 

 cate with accuracy what we obferve in our progrefs. I am flill on my journey, and confcfs 

 that I am very far from having arrived at the place I am defirous of reaching. 



The young men have attended with ardour my courfe of Animal Chemiftry at the School 

 of Medicine. Nothing can equal their wifh to learn. The twenty lectures I give on this 

 part of chemiftry, which is fo new, produce, as 1 fee, a great movement in this branch of 

 the ftudy of nature. But I moderate their enthufiafm as much as I can. I fear left by 

 too much precipitation this beautiful machine fliould be broken in my hands. It would be 

 much to be regretted if expectations fojlch and fo happy were to be diffipatcd in fmoke; and 

 this will not fail to happen if tlie edifice be built on hypothefes, or too much hafte be made 

 in conftruftion before the materials are ready. I colle£l them by degrees, but they are ftill 

 too fcanty to rifk the formation of a fyftera. Yet, to fpeak plainly, I think there are few 

 chemifts who pofTeCs more fadts than myfelf on the animal analyfis : but they are not yet 

 fufficiently connected in their relations to each other to form an entire work. If tlie at- 

 tempt were made, it certainly would not be /Ere perenmus, &c. &c. 



VI. 



Ccncerning the Profertia of the Sulphureous Acid, and its Combinations with Earthy and Alkaline 

 Bajis. By Citizens FoVXCSOV and VaV^ELIN. 



Concluded from page 518. 



Sulphite of Soda. 1 X. HIS fait is white, and perfeiftly tranfparent. Its figure a four- 

 Cded prifm, two of the fides being very broad, and two narrow, terminating in dihedral 

 pyramids. Its tafte is cool, and afterwards fulphureous. 



Its habitudes in the fire are abfolutely the fame as thofe of the fulphite of pot-adi, ex- 

 cepting only that it commences its alterations by the aqueous fufion. 



By expofure to the air it efflorefces, and is afterwards converted into fulphat, but lefs 

 fpeedily than the fulphite of pot-a(h. 



It requires four parts of water for its folution -, is more abundantly folubh in hot water, 

 and readily cryftallizes by cooling. 



Barytesj 



