Letter | Published:

“Mental Evolution in Animals”

Nature volume 29, page 428 | Download Citation



I AM as unwilling as Mr. Romanes to continue this discussion needlessly, but inaccuracy calls for correction. Mr. Romanes says that “the glass wall of a tank is not an object upon the solidity of which a skate would be likely to calculate.” If he will read my original account of the incident again, he will find that the skate made himself absolutely sure of the solidity of the glass wall of the tank; he tried hard to seize the food, and failed because he could not get his head through the glass, and there fore his mouth could not touch the food. As for his being unable to see the food when the current lifted it, that is precisely my case. But he saw it clearly enough, and had tangible experience of the conditions, before he adopted the successful device. If the matter is worth noticing, it may as well be described correctly.

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  1. Manchester, February 29

    • F. J. FARADAY


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