Proceedings. 165 



with those generally held. It is a subject upon which the 

 last word has yet to be said. Early last year, Hirn published 

 a work on the Constitution of Celestial Space, in which he 

 enquires into the nature of the medium or agent which 

 establishes and carries on the relationship between the 

 celestial bodies. He concludes that it cannot be matter 

 even in the state of diffuse gas, that space generally is void 

 of matter, and that ponderable matter only exists in distinct 

 forms, as stars in a solid form, and as nebulae in a state of 

 extreme diffusion." 



In the discussion which ensued it was pointed out that 

 Hirn, like Joule, Eaton Hodgkinson, and others was a 

 distinguished example of the not infrequent attainment of 

 great results in science and philosophy by men engaged in 

 commerce and industry as distinct from professional scien- 

 tific avocations. 



{Microscopical and Natural History Section]. 



Ordinary Meeting, February 10th, 1890. 



Professor WILLIAMSON, LL.D., F.R.S., Vice-President of 

 the Section, in the Chair. 



Dr. ALEX. HODGKINSON explained a method of pro- 

 ducing a small vacuous space by pressing the convex 

 surface of a plano-convex lens on to the surface of a plate 

 of glass sunk below mercury. He spoke of its use in 

 enabling him to examine Newton's rings in vacuo. 



