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EIGHT YEARS' OBSERVATIONS OF THE NEW EARTH THERMOMETERS AT 

 THE ROYAL OBSERVATORY, EDINBURGH, 1879-1888. 



Of these gigantic thermometers, with their bottle-sized bulbs, their long capillary 

 intermediate tubes, and their upper enlarged bores for scale-reading purposes, an account 

 of their construction and being placed in position for observation on June 26, 1879, is 

 to be found in Part II. Vol. XXIX. of the Transactions of the Royal Society, Edinburgh, 

 for 1879-80, and it is only proposed in the present place to give an account of their 

 performances since that time. 



But on examining them in May 1888 for that purpose, a melancholy and complicated 

 stumble on the threshold was realised. 



Mr Richard Adie, the head of the optical firm which had supplied the instruments, 

 and the last of that gifted family, — was dead. 



Mr Thomas Wedderburn, the enthusiastic young optician who had succeeded 

 him in the office, and had indeed really performed all the work both of manufacture and 

 emplacement, was likewise dead. 



And an unexpected calamity had befallen the thermometers themselves. This was 

 that five or six years after their establishment, a slow sinking of the shorter thermometers 

 into the soft ground filling the bore-hole in the rock, began to be recognised. I had 

 apprised Mr Wedderburn of this circumstance m the beginning of 1886; and he at once 

 declared his belief that he would be able to pull them up again to their proper heights, 

 and fix them there, when the weather should allow him, in his then already broken state 

 of health, to revisit the top of the Calton Hill. But that favourable occasion never 

 came, and death overtook him somewhat suddenly on August 9, 1886, greatly lamented 

 and much missed in the scientific circle of Edinburgh men, as a native genius who had 

 never enjoyed full opportunity of showing all that he could do for the promotion of the 

 science of his time ; though he had been found equal to every occasion that had actually 

 come before him. 



Since then the downward march of the thermometers has been getting more rapid, 

 and disturbed sideways as well ; so that the two shortest of the four scientific thermo- 

 meters, or f and f, have the upper parts of their scales thrown together, much sunk, 

 and partly jostling the scale of f, which is also slightly sunk ; leaving only t 1 the 

 deepest, and fortunately the most important of all the thermometers, untouched, and 

 uninjured in its originally intended position. 



Meanwhile however the regularity and assiduity of the Assistant Astronomers in 

 taking the observations of each and every one of the thermometers every Monday, was 



