VARIETIES.  87 
somewhat  different.  The  increase  of  weight  was  greater  in  the  colored 
glasses  than  in  the  uncolored,  green  showing  the  largest  increase,  after 
150  days  exposure.  It  is  worthy  of  notice  that  poppy  oil,  after  a  time, 
oxidized  faster  in  the  dark  than  when  exposed  to  colored  or  white  light. 
Oil,  heated  in  atmospheric  air,  oxidized  much  more  rapidly  than  cold  oil. 
The  oxidation  may  be  accelerated  without  heat  by  adding  some  oil 
already  oxidized. — Am.  Drug.  Circ. 
A  Mountain  of  Saltpetre. — Dr.  Harrison,  the  original  discoverer  of  the 
gold,  silver,  copper,  and  lead  mines  of  the  Crystal  Peak  mining  district, 
located  near  where  the  Henness  Pass  road  first  strikes  the  Sierra,  in  com- 
ing this  way  from  Virginia  City,  has  recently  added  to  his  other  dis- 
coveries a  "mountain  of  saltpetre."  This  mountain  is  said  to  exist 
about  six  miles  north-east  of  Crystal  Peak,  and  it  is  claimed  that  there  is 
no  mistake  as  to  either  the  genuineness  or  quantity  of  the  article.  If  it 
occurs  in  such  quantities  as  described,  its  location  must  soon  render  it  of 
great  commercial  value. — Am.  Drug.  Circ,  from  San  Francisco  Mining 
Press. 
Bismuth. — This  metal  has  of  late  years  risen  considerably  in  price. 
Amongst  other  causes,  sjme  journals  have  stated  that,  two  or  three  years 
ago,  a  company  was  formed  to  work  an  invention,  by  which  gold  was  to  be 
made  by  the  transmutation  of  bismuth  into  that  metal,  and  that  large 
quantities  of  the  former  metal  had  been  bought  up  for  this  purpose. 
Whether  such  an  enterprise  was  or  was  not  entered  upon  does  not  appear. 
The  following  is  a  list  of  the  prices  : — 
s.  D. 
1844 
1845 
1846 
1847 
1848 
1849 
1850-7 
1858 
1859 
1860 
1861 
1862 
1863 
1864 
1865 
0  10 
2  0 
to 
S.  D. 
2    0  per  pound. 
0 
4 
3 
2 
2 
2 
2 
3 
4 
6 
9 
11 
11 
10 
10 
0 
3 
6 
0 
6 
6 
6 
6 
6 
6 
0 
0 
6 
6 
4 
3 
2 
2 
2 
3 
6 
0 
6 
o 
4 
6 
9 
20 
6 
6 
6 
6 
0 
10 
11 
11 
Up  to  1844,  a  large  quantity  of  bismuth  was  produced  in  this  country 
from  cobalt  ores  in  the  old  way  of  refining  ;  but  a  new  way  of  treating 
