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Medal of that Society was awarded to him, after a sufficient interval 

 had elapsed to test the utility of the invention, which is declared by 

 the Committee who examined it, " from the numerous testimonials 

 by practical men in favour of the method described, and detailing the 

 superiority over others in use, to deserve the highest mark of the 

 Society's approbation." An honorary medal was soon after awarded 

 to Sir John for a notice of experiments on the Forth and Clyde 

 Canal, on the resistance to vessels moving with different velocities, — 

 a subject of great interest and importance, then newly brought into 

 special notice, from the ascertained possibility of tracking vessels 

 advantageously at a high speed. Amongst other subjects of general 

 interest included in his communications were the application of hot 

 air to warming houses ; of gas to the purpose of illumination, and 

 also to the purpose of heating. These two last subjects, which 

 admit of a great deal of practical sagacity in their study, were 

 for many years almost constantly under his notice, and many of his 

 friends recollect his success in organizing a kitchen in which gas was 

 the chief combustible. 



" It may, no doubt, be matter of regret that Sir John Robison did 

 not apply more of his attention to practical problems, the solution of 

 which would be of extensive value. The truth is, that the occupa- 

 tions of his life in Britain were only pastimes, and he never attached 

 to them a very serious importance. I may mention one instance 

 which came to my knowledge, of a practical suggestion, I believe of 

 his own, which is undoubtedly of much utility. He remarked to me, 

 a few years befoi-e his death, that the construction of astronomical 

 instruments appeared to be much misunderstood by opticians, who 

 are generally by no means skilled in the engineering of structures, 

 or in mechanics on a large scale. Most astronomical instruments, 

 whether large or small, have been, from the earliest times, construct- 

 ed of a multitude of detached fragments, screwed and clamped to- 

 gether, very elegantly, indeed, but with a complete sacrifice of the 

 firmness to be gained by solid castings. For large instruments, es- 

 pecially, Sir John observed that a Manchester machine-maker would 

 turn out a far better article than the best optician in London has the 

 power of making, wanting the necessary implements. I was much 

 struck by the remark, and not long after I heard exactly similar 

 views expressed by Mr Airy, the Astronomer-Royal, who has de- 

 tailed them in an able paper in tlie A'^otices of the Astronomical So- 

 ciety, 13th May 1842, where he describes a zenith sector, construct- 

 ed upon engineering principles, identical with those of Sir J. Robi- 



