V. MANUFACTURES. 659 



As the capacity of the jar is known, at Kudorff 's experiments with this 

 apparatus it contained 8 -80 cc., there will be necessary of potash-lye : 



at 1 per cent, volume of carbonic acid 8 80 cc. 

 at 2 2-88 = 



at 3 3'88cc. 



In order to form a judgment on the exactness of this method, Rudorff filled 

 the jar with hydrogen and carbonic acid of known strength, and thus he 

 obtained : 



Found. Calculated. 



1 per cent. Co., 8 7 cc. 8 8 



2 ' 17-8 17-6 



3 26-8 2G-4 



4 35-1 35-2 



Some consecutive experiments made with illuminating gas, resulted in con- 

 sumption of potash-lye : 



12*0 cc. = l*,36 per cent. 



12-lcc. = l-37 



ll-8cc. = l-34 



The apparatus, of course, is only intended for ascertaining small quantities 

 of carbonic acid, such as is the case with illuminating gas. The other com- 

 ponent parts of gas are of no perceptible influence on this method. 



The analyses mentioned prove this sufficiently in order to secure for a 

 method a certain adoption in practice, which recommends itself just as well 

 by its trustworthy results, as by easy and speedy execution. 



2456f. Tube with Beads to collect the Ammonia in Coal 



Gas as used at the testing stations. E. Cetti fy Co. 



2737. Demby's Amylometer (potato-tester) accompanied 

 by a description and case. J. H. Suckle?', Breslau. 



This instrument is quite new (1875). It is remarkable for its simplicity 

 and accuracy, as well as for the rapidity with which the starchy matter in 

 potatoes can be estimated. Rain water may be employed. 



2738. Stammer's Testing Apparatus applicable to all the 

 processes met with in distilleries, accompanied by a descriptive 

 treatise. J. H. Bitchier, Breslau. 



This apparatus is quite new. It comprises absolutely true standard hydro- 

 meters for the determination of specific gravities, and replaces (for the most 

 part) the purely empirical methods of testing which have hitherto been in use, 

 by rational chemical methods. 



2667. Soleil-Scheibler improved Polarising Apparatus 



(or optical saccharoetmer) for determining sugars. 



Dr. C. Scheibler, Berlin. 



All the instruments exhibited by Dr. C. Scheibler are for the use of chemical 

 laboratories in beet-root sugar refineries. They are described in the " Journal 

 " of the Society for the Advancement of the Beet-root Sugar Industry of the 

 " German Empire," edited by the exhibitor, and are used in the chemical 

 laboratory of the society of which Dr. C. Scheibler is the director. 



The Soleil-Scheibler Polariscope, serves for the determination of the optical 

 rotary power of sugar solutions, besides ascertaining quantitatively the amount 

 of the sugar contained therein. The improvements made by the exhibitor 



Tt * 



