Letter, regarding the physical properties of ice from William Thomson to [George Gabriel] Stokes Thomson writes regarding an article he has recently read about in the Proceedings of the Royal Society, John Tyndall's 'On some physical properties of ice', which concerns the effects of radiant heat upon ice, the effects of conducted heat upon ice, the air- and water-cavities of ice and the effects of pressure upon ice. Thomson suggests that Tyndall's findings 'afford direct ocular evidence' of his brother James's theory of the plasticity of ice, which had been abstracted in a previous volume of the Proceedings. He goes on to provide his own physical explanation of the veins in glaciers and of the lamellar structures which Tyndall suggests may be induced in ice by pressure. Annotations in pencil throughout. Subject: Physics / Chemistry Received 23 January 1858. Written by Thomson in Glasgow [Scotland]. A version of this letter was published in volume 9 of the Proceedings of the Royal Society as 'Remarks on the interior melting of ice. By Professor William Thomson, F. R. S. In a letter to Professor Stokes, Sec. R. S'. 21 January 1858