34 PETER GUTHRIE TAIT 



Association, the Natural Philosophy class room was the haunt of Section A ; 



and Stokes, Helmholtz, Kelvin, and Tait sat side by side on the platform 



through most of the forenoon sederunts. The afternoons, however, were 



frequently given up to less formal gatherings. On one such occasion 



Mrs Tait's drawing room was converted into a lecture hall with lantern 



and screen ; and C. V. Boys gave a seance of his flash photographs of the 



aerial disturbance produced by a bullet shot from a pistol. At another 



gathering which was purely social Mrs Tait, to make sure of the tea being 



absolutely perfect, had a kettle " singing " merrily on the open fire. Stokes 



and Kelvin were seated on a couch conversing diligently with a lady whose 



knowledge of Japan and Japanese students was interesting them when 



suddenly a sharp hissing sound was heard above the talk and laughter which 



filled the room. "See" said the calm contemplative Stokes pointing with 



his finger, " the kettle is boiling over " ; but Kelvin, who was furthest from the 



fire, leaped forward in his alert eager way, drawing out his handkerchief as he 



went, and lifted the kettle off just as Mrs Tait herself reached the hearth rug. 



On another occasion, when the meeting of Section A was in full 



swing, Tait, wishing to show Helmholtz and Kelvin some of the experimental 



work which was in progress at the time, led them out quietly through the 



door into the apparatus room behind the platform and then down to the 



basement. Here in the large cellar containing the Admiralty Hydraulic 



Press he had some compression experiments going on ; and in an adjoining 



cellar I was experimenting on magnetic strains. While Helmholtz and 



Kelvin were inspecting the arrangements and asking questions about the 



results a message came from the Secretaries of the Section demanding 



the presence of the three truants and especially of Lord Kelvin. Kelvin, 



however, was too eager over the problems of magnetic strains to pay 



immediate heed to the summons. Meanwhile Section A sat in silence 



like a Quaker's meeting. After a few minutes, a second and urgent 



message was sent to the effect that an important discussion in Section A 



could not be begun until Kelvin re-appeared on the platform. Reluctantly 



he tore himself away from the fascination of the research room, mounted 



the long stair, took his seat along with Helmholtz beside the President, 



and began almost immediately to occupy himself with a model on which he 



was to discourse an hour later. 



In 1890 Tait tried his utmost to prevail upon Helmholtz to give the 

 Gifford Lectures on Natural Theology in Edinburgh University. His letter 

 of entreaty was as follows : 



