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Bea. eae 
81 
you will interest American astronomers as far as you can, 
for I flatter myself that observations will be instituted this 
year at European observatories ; and, indeed, I am sure that 
a greater number of accurate meridian observations are 
likely to be made during the months of September, October, 
and November than is common. For the results and suc- 
cess of 1847, it is much to be desired that the few delicate 
meridian instruments in the southern hemisphere should be 
brought to co-operate with us; and this, perhaps, it is in 
your power to facilitate. Of equal consequence will be 
micrometer observations from the same section of the globe; 
but as the latter require no permanent observatory, and only 
a chronometer, a telescope fitted with a micrometer, and a 
knowledge of the neighboring stars, such observations may 
well be made by travellers. Whether there will remain 
time prior to the eastern period for the necessary instruction 
of voyagers to the southern hemisphere, I am not able to 
determine.” 
“This letter,” says Gilliss, in the history of his expedi- 
tions, “bears date 17th of April, but was not received until 
the early part of July, and the next eastern stationary term 
Was to occur in September. On conference with the late 
able astronomer, Professor S. C. Walker, he suggested the 
immediate publication of the letter, as the mode most expe- 
ditious of making it generally known, and, in accordance 
With his advice, printed copies of a translation were for- 
warded to all the astronomers and observatories of the, 
- United States, with as little delay as possible. There was 
too little time in which to perfect arrangements for more 
extended co-operation at that conjunction, and Dr. Gerling 
Was shortly notified that the distribution of his letter was 
Probably all that I should be able to do in the work for 
1847. But, to prove my interest in the prosecution of the 
