142 On the so-called " Inactive" Condition of Solids. 



had not had time to become active by exposure to the air. I say 

 that they were active, as active as Nature's chemically clean 

 surfaces are, more active in fact than if they had been exposed 

 to the air. It is true they did not disengage gas ; the adhesion 

 of the liquid was too perfect for that ; and it was necessary to 

 tame down the adhesive force in order to apply to them any one 

 of what I cannot help thinking are the mistaken terms active, 

 catalytic, and dynamic, as used with reference to this class of 

 phenomena. 



The ingenious experiment on which M. Gernez chiefly relies 

 for the success of his theory, seems to me to require quite an- 

 other explanation. A narrow tube, closed at one end and ren- 

 dered " inactive '■' on the outside, was lowered full of air into 

 the gaseous solution. " Gas adhered to the column of air which 

 the tube contained, forming quickly a large bubble, which was 

 disengaged ; then another was produced, and so on. The gas 

 formed, then, only at the point where the liquid touched the co- 

 lumn of air." "From this experiment," says M. Gernez, 

 " which I have varied in several ways, it may be concluded that 

 air sets up the disengagement of carbonic acid." Had M. 

 Gernez made the inside of his tube as "inactive" as the out- 

 side, I think he would have found that the column of air had 

 nothing to do with the liberation of the gas. 



Exp. 12. A narrow tube 11 inches long was kept for an hour in 

 a quantity of spirits of wine 5 inches deep. It was then washed 

 in water, and closed at the top with the finger, and so just 

 dipped into a fresh quantity of soda-water. There was no dis- 

 engagement of gas. The tube was lowered to various depths 

 with the same result; the finger was then removed, so that the 

 solution could enter the tube. There was no liberation of gas 

 until the immersion of the tube just exceeded 5 inches; and 

 then, at and about the boundary line marked by the spirit, 

 there was a liberation of gas, both on the inside and the outside 

 of the tube. The solution was 6 inches deep ; the tube was 

 chemically clean for 5 inches of its length both inside and out. 

 Above this there was 1 inch of the tube that was not chemically 

 clean, which liberated gas. The tube was taken out, wiped with 

 a duster, drawn through the hand, and again inserted into the 

 solution. The whole length of 6 inches was now covered with 

 gas-bubbles, while a length of 5 inches on the inside was free 

 from them as before. 



I cannot resist the conclusion to which these experiments lead 

 me, that the so-called " active " condition of solids in liberating 

 gas from solutions is a lowering of the adhesive force of such 

 solids for liquids, in consequence of want of chemical purity. 

 Make the solids chemically clean, and the solution adheres to 



