

Calculated. 







Calculated. 



50' 



64° 13' 



& a d, 010 a 021 =39° 



30' 



39° 16' 



20 



18 55 



dA c, 021 a 001=44 



45 



44 50 



30 



56 5*7 



Ca e, 001 a 021=51 



25 



51 22 



40 



20 20 ' 



e*b f , 021 a 0.0=44 



25 



44 32 





22 50 



p~ e, 111 a 021=46 





46 16 







20 8 



r ^ <?, 101211 a 021=43 





42 49 



10 



32 59 



. r a e, 132 a 021=24 



15 



24 36 



15 



41 31 



e^ 7T, 021 a 152=20 





20 8 





33 43 



e a p, 021 a 131=32 



30 



33 42 



45 



51 11 









136 Genth and Penfield — Lansfordite, Nesqiiehonite, etc. 



Z>aM, 010 a 110=63 

 Ma Jc, 110a310 = 20 

 WaM, 110 a U0=56 



<2a x, 021 a ± 32=21 



x* y, 132 a 111=24 



y* z, 111 a 312=20 



y* /, 111 a 201=33 



/a«i, 201 a 10=41 



Oa o, 001 a 112=32 



Ca n, 001a 111=56 45 



At one edge of our crystal, near the top and middle in fig. 

 15, we notice a little indentation where three small faces f, z 

 and y form zone, a few millimeters to the right we again find 

 z and y but separated from the former by a curved stalactitic 

 surface and also by the pyramids n and o. The small facey is 

 very perfect and is here observed for the first time. It has a 

 very simple symbol 2~01, 2-1 and is readily determined by its 

 angles with the faces m and y in the zone. Another feature 

 of this crystal is the highly developed zone p, r, e, where we 

 notice for a second time the pyramids tz and p. The pyramid 

 p is present only as a very small face but gave a distinct re- 

 flection, the pyramid z however, which is only a few degrees 

 removed it is a face of considerable size. The symbol 10 12 11 

 is an unnatural one and may be regarded as questionable; it 

 would not have been accepted if it had not been that the re- 

 flection* from it was followed by a distinct reflection making 

 the proper angle for the pyramid p. The pyramid n is in two 

 levels separated by the zone of small faces/ 1 , 2, y; to the 

 right of this zone, see flg. 15, we notice both and n, to the 

 left only n. 



Recapitulation. 



The measurements which have thus far been given were ob- 

 tained from thirteen crystals ; from the material which was 

 sent to New Haven a few other fragmentary ones could have 

 {been measured but they did not seem to offer anything new or 

 of special interest. Owing to the curious combination of sta- 

 lactite and crystal there is no decided crystallographic habit 

 which can be mentioned as characteristic of our mineral nor in 

 those specimens which are decidedly stalactitic is there any 

 definite relation between the axis of the stalactite and the 

 crystallographic axes for in figures 11, 12 and 13 the faces 

 which terminate the stalactite mostly intersect the end of the 

 vertical axis and in fig. 4 its positive end ; in figs. 5 and 6 they 

 intersect the negative end of the macro axis and in fig. 7 its 

 positive end. 



In criticising the crystallographic results it must be borne in 

 mind, that none of the crystal were well suited for measure- 



