1826.] making a minute Survey of the Heavens. 133 



whole will probably be finished by the time assigned by the 

 Academy for completing the work, viz. the 1st January, 1829. 



I ought to apologize if I have been too prolix, and I hope 

 you will ascribe it to the desire I have to insure also the appro- 

 bation of the Astronomical Society. I am much flattered that 

 you should have entertained the same opinion with me, as to 

 supplying astronomers with sheets already prepared ; — a method 

 which, if it could be executed, would certainly be preferable. 

 On my first coming here, .and on being made acquainted with 

 the views of the Academy, I thought it right to propose this 

 idea to my fellow academicians ; but having made trial of the 

 time necessary for the execution of such a plan, I have been 

 induced to alter my opinion. M. Harding's maps, — a work 

 whose merit is perhaps not sufficiently known, — embrace nearly 

 the half of the stars that have been at present observed ; or 

 perhaps about one-third : nevertheless they have occupied this 

 industrious astronomer almost twenty years. Taking into the 

 account that part of the heavens which is not comprised 

 between — 15° and -r 15°, I believe that 10 or 12 years would 

 elapse before one person, or even two co-operating for the same 

 purpose, would be able to finish both the drawing and the 

 engraving of the maps. My present employment does not 

 allow me to apply exclusively to it, even if I had the confidence, 

 which certainly I have not, that every thing would succeed well. 

 The undertaking would in such case be put oif so long that per- 

 haps we could never be certain of finishing it. By dividing this 

 work, however, into hours, we may hope that the honour and 

 character of each astronomer that may take a share in it, will 

 induce him to carry his own portion to the greatest possible 

 degree of perfection. And if the uniformity in the drawings 

 should not be so great as if a single person had carried on the 

 whole, yet we shall gain in point of time : and likewise have the 

 advantage of making a revision of all that part of the heavens in 

 the course of two years, — a period very little longer than that 

 which would be required to execute a fine engraving of the 

 maps. 



In No. 93 of the Astronomische Nachrichten published by M. 

 . Schamacber, there i^ a description of a machine which M. de 

 Steinheil has tried and found very convenient and correct for 

 marking the precise place of an observed star. If all the 

 astronomers would make use of it, it would produce results 

 having a great degree of conformity amongst the whole. 



I remain, dear Sir, with the greatest consideration, -. 

 Yours, ifvc. J. F. Encke. 



