**Nb** Va Vb FIG.

COLUMBIUM, or Niobium (symbol Cb or **Nb**, atomic weight 94), one of the metallic elements of the nitrogen group, first detected in 1801 by C. Hatchett in a specimen of columbite (niobite) from Massachusetts (Phil.

Along CA and DB, on the same side of MN, take MA' = CA, **NB**' = DB; and join A'B'.

SF) The lines MA, **NB**, PC,..

If BN, CP, DQ, FS, GT are the perpen diculars to AE from the angular points, the ordinates **NB**, PC,..

3, if AN and **NB** are regarded as positive, then SF, TG, ET and SA are negative, but the products ET.

Along the base-line, and the lengths and directions of the offsets **NB**, PC, QD,.

Libation bs.t bs bs L vase it, cord on wz wz wz J stick ~J7 basket **nb**.t **nb** r~ looped ?

**Nb** Having scattered the Lincolnshire bands, he suddenly turned upon Warwick with his army, and caught him wholly unprepared.

Taking the case where the motion is strictly in two dimensions, we may write as the polar equation of the surface at time t r =a cos **nB** cos pt, (4) where p is given by p2 = (n3_ n)..