Davidson.] 290 [December. 



wear, on account of the erroneous construction of the Y's and the 

 tangential contact of the pivots with them. 



To prevent torsion between the shorter arms and the level cylinder, 

 triangular stay-pieces are introduced at each right angle of the join- 

 ing ; and for increased security, they may be introduced upon the 

 upper or under sides. 



This level, with the level-tube and supporting cylinder, and adjust- 

 ments of the same size as the present striding level", permits measure- 

 ments for the determination of the inclination of the transit axis, and 

 for the inequalities and irregularities of the pivots, through a range 

 of 45° on each side of the zenith. Of this arc, 70° have not here- 

 tofore been reached for these corrections, except in part by reflection 

 observations, which are, however, practically excluded from use with 

 the portable instruments and in the temporary observatories of the 

 Coast Survey ; and especially on trips for difference of longitude by 

 chronometers, when the instruments are frequently set up hurriedly 

 for a few hours only at each station. 



George Davidson. 



The attention of the Society being directed to the subject 

 of the expected meteoric display on the 13th or 14th ultimo, 

 several members spoke on the subject, and generally expressed 

 the opinion that the earth was at the time not in a position to 

 render the meteors visible in this longitude to any great ex- 

 tent. 



Mr. Briggs referred to the agglomeration of small coal as 

 a manufacture in successful operation in Belgium, as an in- 

 stance of the feasibility- of agglomerating the fine coal of 

 Pennsylvania. 



Pending nominations Nos. 552, 553, 554, and 557, and new 

 nominations Nos. 558 to 567, were read. 



On motion of Mr. Fraley, the President was empowered 

 to fill any vacancy that might occur in the Committee to aid 

 the Trustees of the Building Fund. 



And the Society was adjourned. 



I 



