Errata in Weisse's Planetary Tables. 245 



In this example, it will be seen that I have interpolated 

 for the odd minutes, in order to show the method of obtain- 

 ing, in all cases, the correct values of the logarithms of the 

 table required : but it is evident that, with the exception of 

 the logarithm of B, this was unnecessary ; and that no error 

 would have arisen if we had taken, even in all the quantities, 

 the tabular values opposite to the nearest tenth minute. And 

 I would further remark, that it will seldom be necessary to 

 extend the series to so many terms as are here given : since 

 we may generally stop at the third difference (and sometimes 

 even at the second difference), if we see that the subsequent 

 differences are not sufficiently large to affect the result. 



Before I conclude, I would remark that the logarithms of 

 D and E were calculated for every half hour only, and the 

 values interpolated for the intermediate ten minutes, using 

 second differences in the computations. 



F. B. 



XLII. Errata in Weisse's Planetary Tables. By A CORRE- 



SPONDENT. 



number of individuals who in this country are en- 

 * gaged in science, except in what may not inaptly be de- 

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* While in Russia, a nation which we are accustomed to contemn ,as 

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f This work, indispensable to practical astronomers, consists of one 

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 as a model for all books of tables, and is published by Bachelier of Paris, 

 and Treuttel, London. 



same 



