102 Prof. Forbes's Letter respecting two Papers 



Table II. Table III. 



Thermometer. 





Log. DifF. 





Log. 



DifF. 



60 



0-00000 









50 



0-00000 





49 



0-00094 





51 



9-99906 





48 



0-00190 





52 



9-99811 





47 



0-00285 





53 



9-99717 





46 



0-00380 





54 



9-99623 





45 



000476 



96 



55 



999529 





44 



0-00573 





56 



9-99434 



94 



43 



0-00668 





57 



9-99341 





42 



0-00764 





58 



9-99548 





41 



0-00861 





59 



9-99154 





40 



0-00957 





60 



9-99061 





39 



0-01053 





61 



9-98969 





38 



0-01151 



98 



62 



9-98875 





37 



0-01248 





63 



9-98783 



92 



36 



0-01346 





64 



9-98690 





35 



0-01444 





65 



9-98598 





34 



0-01541 





66 



998506 





33 



001640 





67 



9-98414 





32 



0-01738 





68 



9-98323 





31 



0-01837 





69 



9-98231 





30 



0-01935 





70 



9'98140 





29 



0-02033 





71 



998049 





28 



0-02133 



100 



72 



9-97958 





27 



02232 





73 



9-97867 





26 



002331 





74 



9-97777 



90 



25 



002432 





75 



9-97686 





24 



0-02531 





76 



9-97596 





23 



002630 





77 



9-97506 





22 



002730 





78 



9-97416 





21 



002832 



102 



79 



9-97326 





20 



0-02933 





80 



9-97237 





Barometer. 





Log. 



Diff. 



In. 







31 



0'0]424 





30-9 



0-01248 





8 



0-01143 





7 



0-01002 



142 



6 



0-00860 





5 



0-00718 





4 



00575 





3 



000432 



144 



2 



0-00289 





1 



0-00145 





30-0 



0-00000 





29-9 



9-99855 





8 



9-99709 





7 



9-99503 





6 



9-99417 



146 



5 



9-99270 





4 



9-99123 





3 



9-98075 



148 



2 



9-98826 





1 



9-.98677 





29-0 



9-98528 



150 



28-9 



9-98378 





8 



9-98227 





7 



9-98076 





6 



9-97924 





5 



9-97772 



152 



4 



9-97620 





3 



9-97^66 





2 



9-97313 





1 



9-97158 





28-0 



9-97004 



154 



XVII. Letter to Richard Taylor, Esq., with reference to two 

 Papers in the Philosophical Magazine for January^ 1840. 

 By James D. Forbes, Esq., F.R.S.S., L. Sf Ed., <^c. 



My dear Sir, 

 JN order that your readers may be aware why I do not 

 ■*■ answer Mr. Potter's animadversions in the January Num- 

 ber of the Philosophical Magazine, I would request you to 

 insert the following letter which I addressed to him after 

 reading his communication. 



" My dear Sir, « Edinburgh, Jan. 8th, 1840. 



" I have read with some pain, and at least equal surprise, 

 some observations by you on photometry, stated to have been 



