(1688) In the opening of the flask I burned one - fourth of an ‘ aas ’ ' s weight of sulphur .The moment these Moths in the glass became aware of the smoke or the smell of the sulphur , they were flying very fast to and fro inside the glass , but this flying lasted only a short time , for they all fell down and moved their legs for only a short time , and died shortly afterwards .Three hours after this I took the Moths out of the said glass , and I put live Moths in it , with the intention also to kill the latter Moths with sulphur : But when I was then ready to get the sulphur to burn , I saw that all the little Moths were lying dead in the glass , which was caused only by the sulphur that was still in the glass .