of Latitudes for Local Attraction. 315 



has for so many years occupied a position at the head of the 

 extensive Geodetic Survey operations of the Imperial Staff, the 

 Academy thought that Herr Dollen's report by itself should 

 hardly be considered conclusive, and resolved to defer the 

 decision of the matter until my return from abroad. At a 

 meeting on the 19th of October the discussion was resumed ; 

 and I had then the opportunity of assuring the Academy that 

 I quite agreed with Herr Dollen's opinion in every essential 

 respect, and only differed from him somewhat as to the im- 

 portance of certain details. After my remarks on these had 

 been submitted to the Class, the matter again underwent mi- 

 nute discussion, as the result of which the Academy passed 

 the resolution that no action need be taken on General Schu- 

 bert's proposal, and that Herr Dollen's report and my sub- 

 sequent remarks on it should be arranged in the form of an 

 essay, in order to bring the grounds for this decision into 

 general notice. 



In executing this task we feel ourselves obliged to refrain 

 from criticism upon the farther contents of the above-men- 

 tioned paper of General Schubert's, as not directly appertaining 

 to the subject, and will therefore confine ourselves simply to 

 the consideration of the proposal in question. 



Herr von Schubert expressly states that the Russo-Scan- 

 dinavian arc, as it is now presented to the scientific world, 

 might till a few years ago truly lay claim to the title of 

 a completed work, and that it is only the appearance of the 

 English book mentioned below* (marking, as it does, an era) 

 that has materially altered the state of the case. The next 

 thing, therefore, is to ascertain in what respect the state of 

 the case is altered by the appearance of this work. It ranks 

 unquestionably among the most important publications of 

 our time in the region of geodetic literature. The care and 

 circumspection evinced in this work, in the preparation of 

 the data of observation which have been collected during the 

 last three quarters of a century, and in the deduction of re- 

 sults as well for the English arc in particular as for the figure 

 of the earth in general, fully entitle it to rank as a model. 



As regards the arc, one material difference between this 

 work and others is pointed out in the work itself, viz. 

 (p. 742) that not, as is usual, has a selected triaiigulation, 

 following as closely as possible the direction of the meridian, 

 been alone considered, but the entire network of triangu- 



* Ordnance Trigonometrical Survey of Great Britain and Ireland. 

 Account of the Observations and Calculations of the principal Triangu- 

 lation &c, drawn up by Captain A. E. Clarke, under the direction of 

 Colonel H. James. London, 1858. 



2A2 



