IN the interesting letter by Mr. A. H. Drew, under the above heading, in NATURE, February 20, it is suggested in the last paragraph that certain substances called auxetics which caused the development ...

I WAS interested in Mr. T. Goodey's letter under the above heading in NATURE of March 13, but should like to make a few remarks thereon. Hay infusion, which Mr. Goodey states caused the excystation of ...