Minutes of an ordinary meeting of the Royal Society Dr Wilkins experiments of blown bladders made, whose particulars are in the Register book. Mr Croone produced a glass jar full of powder of the bodies of vipers and a galley pot full of the powder of only hearts and livers of vipers. Ordered that Dr Wilkins to cause pipes of several bores to be made, to try the experiment of blowing up weights. That Sir Robert Moray to bring at some time some of the humble and sensitive plant's seeds. Ordered that Dr Whistler bring in writing his thoughts of gravitation and springs. Mr Henshaw brought in spirals of nut-trees shewing thereby that they grow snail wise. 31 July 1661