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Thus, I have said that the logarithms have been calculated with 
14 decimals, but with the view only of having 12 exact; and this 
degree of accuracy is almost absolutely secured. 
Y. Far be it from me to entertain the idea of blaming the inten- 
tions of Mr Edward Sang. I am convinced that he has had no 
other desire than to reach the truth. The scientific liberality of 
England is too well known, and has recently been too well shown, 
by the publication of Hansen’s Lunar Tables, to allow us to sup- 
pose that a savant belonging to that nation would deliberately seek 
to discredit a great French work, concerning which he has been ill- 
informed. 
It has not depended, and it will not depend on me, to throw 
more light on a subject which has occupied me for several years. 
In 1857 I presented to the Academy of Sciences of Paris a very 
extensive memoir on the Theory of Logarithms, on the construc- 
tion, and on the use of Logarithmic Tables. In this work I have 
reviewed everything important that has been done from Napier’s 
dowm to our times. Notably, I have explained with many details 
the work of Briggs, and the monument erected under the direction 
of Prony by the Bureau du Cadastre. It would make a quarto 
volume of some 200 pages; I have found no one willing to bear the 
expense of the impression. 
I would willingly extract from my work anything that would 
interest the learned ; and to prove this I do not think I can do 
better than annex to this note the errata which I have compiled 
for “ Yega’s Thesaurus Completus.” I have no recollection of 
having published it before. 
I have prepared also an errata for Briggs’ u Arithmetica Logarith- 
mica,” which contains about 300 entries, but its publication would 
need to be accompanied by some details which I am just now unable 
to give. I would remark only, that M. Sang does not seem to have 
read in my memoir inserted in tome IY. des Annales de l’Obser- 
vatoire de Paris the passage in which I point out the limited extent 
of the comparison of Briggs’ tables with those of the Cadastre made 
by MM. Letellier et G-uyetant. “ The comparison made by 
MM. Letellier et Gruy^tant extended only to 12 figures. It might 
