Asfronomy. 



265 



This fecula has been many times commended to attention since 

 Bachelier in 1615 brought the tree from Constantinople, (it coming orig- 

 inally from Southern Asia). Parmentier, Baume and others sought suc- 

 cessively to bring it into general use. But the mode of manufacture 

 was not satisfactory, partly because of the presence of a resinous sub- 

 stance which was separated with difficulty, and partly on account of the 

 dark shell of the nut, which it was thought necessary to remove before 

 extracting the fecula. 



In the new process, the nuts are grated with the bark on, and treated 

 like the potato with its skin ; the material is then washed in water as 

 easily and as economically as the potato, so that the price is not above 

 20 centimes per kilogram, the cost of cultivation and manufacture being 

 included. 20,000 kilograms of the fecula manufactured this year with the 

 apparatus that is used for the potato have settled the question of its im- 

 portance. 



Astronomy. — Among the changes at the Observatory at Paris, the es- 

 tablishment of the " Annals of the Observatory" is worthy of mention. 

 The object of this periodical is to publish the results of observations of 

 every kind connected with the Observatory, and also of such tables and 

 reductions as are indispensable to give the results an actual scientific 

 value. The completion of the tables to facilitate the discussion of the 

 observations and aid in comparing with theory is making rapid progress. 

 The first volume of the publication is just from the press. It contains 

 the Report of M. Leverrier addressed to the French Government, and fol- 

 lowing this, a statement of the system of organization now established. 

 There are next, astronomical researches of various kinds, with the prin- 

 cipal formulas for the calculation of functions. 



This work, whose numerous mathematical formulas render it of diffi- 

 cult execution, goes out almost without a fault from the ably conducted 

 press of Mallet-Bachelier. 



View of a part of the surface of the Moon. — M. Secchi, Astronomer at 

 Rome, has sent to the Academy a photographic view of the part of the 

 moon's surface in which stands the crater named Copernicus. The scale 

 is about s-g-^xnro- The photograph was not taken direct from the moon, 

 but from a design executed with great care on a somewhat larger scale, 

 and having for its base a micrometric triangulation of the principal points 

 of the area. The details were brought out with a lens magnifying 760 to 

 1000 times: the work, seemingly easy, was attended with great difficul- 

 ties, on account of the change in the shadows with every hour, the moon's 

 libration and change of distance. To avoid all these difficulties a general 

 sketch was first made under the most favorable light and view for 

 marking out the crater, such as is ordinarily had when the moon is ten 

 days old. After this, the details were separately made out, and then all 

 were combined in their true relations, so as to make the complete sketch. 

 The result thus reached was corrected by several examinations made from 

 the first point of view. A professed draughtsman was occupied with the 

 work during seven consecutive lunations, without counting the time em- 

 ployed previously in practicing preparatory to the work. 



As the drawing was intended to represent the great central crater, the 

 area around is not yet filled with all the details that may be introduced. 



SECOND SERIES, VOL. XXII, NO. 65. SEPT., 1856. 



34 



