On a new Apparatus for preparing Muriatic Acid. 21 



adaptation of that change of colour to tlieir better security, are 

 coincidences out of the course of chance, and not easily ex- 

 plained bv our present state of physical knowledge. 

 I have the honour to be, dear sir, 



Your much obliged and obedient servant, 

 To the Einht Hon. Sir Joseph Banks, Anthony Carlisle, 

 Bart. K.B. P. U.S. &c. 



VI. Description of a new Apparatus for prep ar ins: "^''th Faci- 

 lity and CEconomy pure Muriatic A?id. By L. V. Bru- 

 &NATELLI. Read in the Italian Institute*-. 



yjp all the chemical apparatus generally used for preparing the 

 acids, unquestionably that employed in the manufacture of mu- 

 rijitic acid is the most complex and CNpensive. For this pur- 

 pose, a large tubulated retort, a balloon glass with two necks or 

 a tubulated globular glass, Woulfe's apparatus, tubes of security, 

 and lutes of the best qualitv, are required. The operator also 

 requires rauch dexterity to unite these divers pieces, to conduct 

 the operations, and great care in transferring the concentrated 

 muriatic acid from the balloon glass to the bottles in order to 

 avoid its noxious fumes. However well the |uocess may be 

 conducted, the acid, by the common method, still retains a dirty 

 yellow coloui-, and is injured by sulphuric acid. The means 

 adapted for purifying it are very troublesome, and are likewise 

 attended with a considerable loss of acid. 



Considering that all muriatic acid is disengaged from com- 

 mon salt in the state of gas, and that this gas combines very 

 rapidly with pure water, I have demised a simple apparatus with 

 which it can be condensed by water, purified from the sulphuric 

 acid and the greater part of the coloui ing matter. Having made 

 the experiment several times, I have found it always answer per- 

 fectly my expectations. This new apparatus consists of only 

 three pieces : 1st, a matrass which may or may not be tubu- 

 lated ; 2dly, a bent tube made in the manner represeftted in 

 fig. 8. Plate I. which constitutes the most important part; and 

 3dly, a common glass receiver rather narrow and high, its 

 mouth ground and made to receive a ground stopper. In the 

 matrass a, fig. 1. placed over a sand-bath, put, for example, 

 eight ounces of clean culinary salt dried to a coarse powder. 

 In the bent tube lib, introduce a solution of muriate of barytes, 

 which should be raised to the same height in the two arms e, 

 forming its curvature. Pour five ounces of sulphuric acid on 



* From Bni'^ivitelli's Giortiale de Fisiia, Cfiimica, Sturia Nuturale,&c, 

 vol. vii. April liSli, 



B3 the 



