Mechanical Science, 401 



Journal, that a plan for a minute survey of the heavens had been 

 proposed by, and partially executed, under the superintendence of 

 the Royal Academy of Sciences of Berlin. The nature of this 

 plan we previously detailed ; and stated at the time, that two maps, 

 one by M. Inghirami of Florence, the other by M. Harding of Got- 

 tingen, executed in accordance with it, had been delivered to the 

 Academy. Since then, a third map has been contributed by a 

 countryman of our own, the Rev. T. Hussey, with the assistance and 

 co-operation of the Rev. F. Dawson. Relative to this work, which 

 required three years for its completion, the following letter, ad- 

 dressed to the former of these gentlemen, by M. Encke, secretary 

 to the Royal Academy of Sciences of Berlin, has been communi- 

 cated to the Astronomical Society of London: — 



" You have doubtless, Sir, been surprised at not receiving any 

 earlier information of the arrival of the map and catalogue of stars 

 which you delivered to the Prussian ambassador in July last. 

 You will excuse me, however, on my assuring you, that the parcel 

 did not reach my hands till the 22d of October. This great delay 

 has, fortunately, not occasioned injury to the drawing you so 

 zealously executed. The whole was in very good condition. It is 

 at present at Konigsberg, whither I sent it immediately after having 

 compared the sixty squares, which are common to yourself and M. 

 Harding, from whom we have been so fortunate as to receive the 

 XVth hour. 



" The agreement of the observed stars is almost perfect. As to 

 those which are added, it appears, that the faintness of their light 

 has not permitted so exact an accordance. Sometimes M. Harding 

 has thought right to insert a few points which are not to be found 

 in your map, sometimes the latter contains a few more than M. 

 Harding's map. I hope it will soon be in my power to inform you 

 of the opinion of my colleagues, both as to this map and to your 

 obliging offer, to undertake another part of the heavens, if that 

 should be necessary for the completion of the work — but I am 

 unable to anticipate the decision of the committee. I would not 

 longer delay removing your anxiety as to whether a work on which 

 you had bestowed so much valuable time had reached us safely. 

 Requesting you to accept the assurance of my high esteem, 



44 1 have the honour, Sir, &c. 

 Berlin, November 4, 1829. "Encke." 



When the variable nature of this climate is considered, and the 

 particularly unfavourable state of the weather during these last two 

 seasons, when the XlVth hour was above the horizon, we are by 

 no means surprised, that a discrepancy should exist in inserting in 

 a map stars below the ninth magnitude, when, moreover, those 15° 

 south of the equator, did not attain at Chislehurst, where the com- 

 parison between the map and the heavens was instituted, a suffi- 

 cient elevation to be free from the vapours of the horizon itself. 



