390 Dr. A. Krantz on a new Mineral named Orangite. 



will therefore be obviously greatest at the pole^ aud may be said 

 to vanish at the equator. 



It may be interesting here to ascertain what the deflection 

 ought to bej solving the question by the apparent deviation of 

 the plane of the pendulum in 34". The tangent of the arc of 

 vibration maybe looked at in the same light as the line drawn from 

 the gun to the shot at any moment of its flight ; for there is 

 nothing in the rotation of the earth to cause this tangent to have 

 an angular motion in a horizontal direction. 



8'-513 = rotation of the earth in 34"nat. sin 52°= -7880108. 



8-513 X •7880108=6-708=6' 42" 28"' deviation in 52 lat. 

 in 34". 



Length of cu*. arc of 6' 42" 28"' = -0019512 of radius rad. 

 = 5600 yards. 



5600 X -0019512 = 10-926 yards, which is the deflection. 



Taking into account that the amount of deflection of the pro- 

 jectile has been determined, in the one case, by assuming the 

 length of a geographical mile to be 2000 yards, and that in the 

 other, viz. in the pendulum experiment, the amount is indepen- 

 dent of the size of the earth, the results are as nearly alike as 

 can be possibly expected. 



I am. Gentlemen, 



Your obedient Servant, 



E. M. Boxer. 



LIX. On a new Mineral named Orangite. 

 By Dr. A. Krantz of Bonn^^, 



THIS mineral has been found only at Langesundfjord near 

 Brewig in Noi-way, and is of veiy rare occurrence. 



It has been analysed by Dr. Bergemann, and is stated by him 

 to contain a new metal which he has named Donarium. [Hia 

 analysis, together with an account of the properties of the new 

 metal, were given in the Philosophical Magazine for June 1850, 

 p. 583.] 



No indications of crystalline form have been observed. The 

 fracture is conchoidal ; structure imperfectly foliated ; transpa- 

 rent to translucent ; colour deep orange-yellow ; streak yellow- 

 ish-white ; hardness between fluor and apatite ; specific gravity 

 5*34 to 5'39. It occurs usually imbedded in felspar, associated 

 with mosandrite, black mica, hornblende, thorite, zircon and 

 erdmannite. 



♦ Communicated by W. G. Lettsom, Esq. 



