340 LETTERS OF 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 1 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, he 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 afforded him impor- 

 tant assistance. 



The individuals enumerated, many of them high 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 r/ortion of the three 



