340 



BENJ. PIKE S, JR., DESCRIPTIVE CATALOGUE. 



the different parts well washed in water, and replaced. Care 

 should be taken to keep the platina slips from injury, they 

 being thin, and the metal valuable. They are packed in 

 black walnut boxes with cover, and handles at the ends. 

 Price, of a series of 4, small size, $4.50 ; large size, $6.50. 



" 6, " $6.00; " $9.50. 



" 12, " $10.00 and $12.00. 



" 12, large size, $16.00 and $18.00. 



" 18, " $24.00 and $27.00. 



Fig 402. 



Fig. 403. 



Fig. 404. 



Apparatus for the Decomposition of Water. (Fig. 402, 

 as above.) This consists of a globe of glass with a neck, to 

 which is fitted a cork having a small aperture at the side 

 for the escape of water ; through the cork is passed two 

 long wires, to the ends of which are soldered platina wires, 

 or a strip of platina plate projecting within the globe for an 

 inch or two, and separated a short distance from each 

 other. If the globe be filled with water, and the wires 

 connected with a powerful galvanic battery, the water will 

 be decomposed, and resolved into its elements, hydrogen 

 and oxygen gases. Pure water has but little conducting 

 power; the addition of a little sulphuric acid, or common 

 salt, will greatly increase the evolution of the gas. 



Price, $0.75. 



Apparatus for collecting the Gases Separately. (Figs. 403 

 and 404.) This consists of a glass vessel having a foot in 

 the form of a bowl, or large goblet, holding about a quart, 



