40 LETTERS OP A CITIZEN. 



(by which I suppose you to mean the several sciences included 

 under the general term of natural history) constitutes the main ob- 

 jects of the expedition, how did it occur that your envoy failed to 

 procure any apparatus for research in this branch, if we except a 

 case of drawing instruments with Cameras Lucidas ? To seven, 

 if not more, of the fourteen gentlemen forming the scientific 

 board, microscopes of the most approved construction, such as 

 are made only in Europe, were, I should imagine, indispensable. 

 But, finding no such articles on the list, I suppose it was con- 

 sidered that everything earthly, aerial, or aquatic too small to be 

 seen with the naked eye was too insignificant for the notice of 

 savans on " any expedition !" 



Again : had the individual deputed, who performed his mission 

 in " the most successful manner," looked into some of the books 

 he brought with him, lie might have learned that, in making 

 magnetic experiments, modern observers think that a rarefied me- 

 dium is highly important, and that nothing is more prejudicial to 

 accuracy in their results than the variable influence of the atmo- 

 sphere. This theory has been amply explained by philosophers 

 in England ; and long series of experiments, testing and proving 

 its correctness, have been made in the United States. The pro- 

 curement of astronomical apparatus, however, may have kept the 

 attention of your agent so constantly fixed upon the heavens, that 

 he unconsciously omitted to notice these trifles connected with 

 earth ! 



Is it to be presumed that you consider the meteorological de- 

 partment well supplied with instruments without some apparatus 

 for investigating the state of atmospheric electricity ? Or, as such 

 apparatus is not named in the list before referred to, are we to 

 conclude that electricity does not form a subject of attention in 

 "any expedition" fitted out under your direction, even when sci- 

 entific pursuits are its "leading objects?" 



The agent very properly returns his acknowledgments to the 

 savans abroad whom he consulted and who afl'orded him impor- 

 tant assistance. 



The individuals enumerated, many of them hi^h in rank, are 

 certainly eminent in hydrography, astronomy, natural philosophy, 

 and as makers of philosophical instruments. This is all very well, 

 so far as it goes ; but why was not some portion of the three 



