416 Life of Count Rumford. 



heat they must be made on purpose. The Collar and man- 

 drel, &c is in hand, but there being but one workman in 

 London whose Lathes I could recommend, and his being so 

 much employed, renders it impossible to get it finished in less 

 than three weeks or a month. The set of Glasses for the 

 Lucernal Microscope must also be made on purpose, which will 

 take nearly two weeks. The collar and mandrel, with screw- 

 tools complete, will come to 5. 15. o, and the set of Glasses 

 for a Lucernal Microscope will be 3. 3. o. 



" P. S. It will be of no use to send the Speculums of the 

 Reflecting Telescope without the brass work, as the goodness 

 of the Telescope principally depends upon their being properly 

 adjusted. 



11 The cleaning of the Speculum would cost about 2$/s. 



"W\- FRASER. 



" In Varnishing any Brass- Work, the Brass is first to be 

 warmed just sufficient to evaporate the Spirits and leave the 

 Wax or Gum on the Brass. It is to be put on as lightly as 

 possible, so as to be all covered. 



.("Received Aug 1 . 6, 1800.") 



It would have been a most gratifying and delightful 

 incident in the life of Count Rumford, if, in fulfilment 

 of the terms of his own cordial invitation, his friend 

 Colonel Baldwin had had leisure at the time to indulge 

 his own earnest wishes by joining the Count in Lon- 

 don, to revive the pleasant memories of their youth, 

 and to enjoy the privilege of such a companionship 

 for introduction to eminent scientific men and for 

 travel in England or on the Continent. But Colonel 

 Baldwin was, in a more limited sphere, serving his na- 

 tive State as faithfully as was the Count in his larger 

 opportunities advancing the interests of practical science 

 for the civilized world. In the mean while Colonel 

 Baldwin was faithful to the highest obligations of re- 



