1822.] Scientific Intelligence. 463 



II. Composition of Formic Acid, ? 



Dr. Gobel saturated distilled formic acid with oxide of lead, and 

 found that the formate of lead contained 24<*5 per cent, of formic acid. 

 In heating 10 grains of formate of lead with black oxide of copper in 

 a glass tube, he obtained S'^ cubic inches of carbonic acid gas, which, 

 according to the state of barometer and thermometer, were equal to 

 2*922 grains of carbonic acid = 0792 grains of. carbon. The glass 

 tube weighed after the experiment 3*55 grains less than before, which 

 would make the w^ater amount to 0*68 grain = 0'0755 grains of hydra-; 

 gen. The composition of 2'4<5 grains of formic acid will, therefore, be 5; 



Carbon 0-797 i 



Hydrogen 0-075 



Oxygen 1-578 * 



2-450 ■ 



The formate of lea^ is composed of 



1 atom oxide of lead. 107*5 



1 atom formic acid 34-9 



1 atom water ...^ 8"45 



150-85 



One atQm of formip acid = 34*9 myst^ therefore, be composed of 



Carbon. .i!'i';^?.^'«'M-.*^w> 11*35 



Hydrogen , 1 06 



Oxygen 22*43 



34-81- 

 Which is equivalent to . 



2 atoms of oxide of carbon 26*4 



1 atom water 8-45 



34*85 



According to Dr. Thomson's numbers, formate of lead would be 

 composed of 



1 atom oxide of lead 112 



1 atom formic acid 37 



1 atom water 9 



158 



and the formic acid composed of 



2 atoms of oxide of carbon 28 



1 atom of water 9 



37 



IH. Effects ofBoracic Acid on the Acidulous Fluates of Potash, S^e. -- 



Dr. Zeise being engaged in some experiments on the fluoboric acid, 

 and on the fluoborates of the alkalies, observed that a solution of fluate 



