ScUnHfic News, Accounts of Bookst &c. 45 



other things) were not In common nearly upon a level whh nurfes in that which it fo much 

 imports them to poflefs— an acquaintance with the powers that operate to the injury or 

 advantage, the deftruftion or prefervation, of the obje£ts of their affeftion. 



The Author further hopes (if he may repeat his own words) to contribute towards pre- 

 venting the " ignorant from tampering with the fick ; towards promoting the afcendancy 

 "of fcience over intrigue; alluring curiofity from the pernicious frivolities of literature, 

 " and elevating the conceptions of men to the level of their higheft interefts." 



As the whole courfe will be conncfted, the tickets will not be transferable — The num- 

 ber of lectures cannot be determined beforehand — But that there may be little chance of 

 exclufion by reafon of narrow circumftances, the fubfcription is fixed at One Guinea— 

 The leflures will be calculated for both fexes and different ages — They will be delivered 

 in the evening, and commence fometime in April next^ — probably near the middle of the 

 month — provided fifty perfons fliall have entered their names by the 31ft; of March. This 

 condition is indifpenfable. Without a tolerably numerous audience, the author prefumes 

 he could beftow his time in a manner more advantageous to the public. 



Subfcriptions received by Mr. Sheppard, Bookfeller, oppoftte the Exchange, with whom 

 conditions for printing a Syllabus may be feen. 



Rodney-Place, Clifton, March 3, 1800. 



Extr.aB of a Letter from M. Fabhroni of Florence, to Cit. Van Mohs, on the Etbiops of Iron, 

 the Formation of Alcohol and Fermentation. [An. de Chim. XXX. 220.) 



Take a pound of iron filings, reduce them to a pafte with water, and put it in acapfcule,- 

 or what is ftill better, a glafs matrafs, kept in a water bath at about 50 or 60 degrees 

 (Reaumur). Pour on it gradually one or two ounces of aqua fortis, rather diluted, or of 

 nitrous acid very much diluted, and continue ftlrring it with a fpatula. It is remarkable, 

 that it undergoes a kind of efi"ervefcence, after which the iron is changed into a very fine- 

 black powder, and oxided to the firft degree of oxidation ; that is to fay, converted into 

 martial ethiops. The operation is performed in lefs than half an hour. If the mixture be, 

 put in a clofed veflel, and not fliaken, but left from evening till the next day,, the furface 

 of the ethiops is found to be covered with a kind of champignons extremely white, and 

 feveral lines high, which are nothing but volatile alkali, or carbonate of ammoniac. The 

 air in the veflel is in this laft cafe, compofed in a large portion of oxigenated nitrous gas. 

 A decompofition here takes place of the water and nitrous acid, both at the fame, time, by 

 the iron which feizes their oxygen, in order to become converted into the oxide ; and the 

 component parts of thefe two liquids, that is, the azote and hydrogen, which being dif- 

 cngaged' at the fame time, meet whilft they are yet in. a ftate of condenfation, or before 

 they have taken thei form of a gas, by combining are transformed into ammoniac. A por- , 



tion. 



