Am.  Jour.  Pharm.  ) 
June,  1875.  J 
Varieties, 
275 
in  quantity,  so  that  soon  after  filtration  the  solution  contained  1*22  per  cent,  5  ten 
minutes  after,  0*59  per  cent.  5  two  days  after,  0*26  per  cent.  5  and  a  fortnight  after 
only  0-2  per  cent,  of  sulphate  of  calcium,  and  this  at  a  temperature  of  2o°-22°  C. 
(68° — 70°  ¥.)—Buchners  Report,  xxii,  p.  483. 
Sulphate  of  Aluminium. — The  best  way  to  examine  whether  it  contains  sul- 
phuric acid  in  excess,  is  by  treating  it  with  strong  alcohol,  which  only  extracts  the 
excess  of  acid.  Sulphate  of  alumina  is  insoluble  in  alcohol. — Hager,  Ph.  Centralbl.y 
xiv,  p  330. 
Oxide  of  zinc  sometimes  becomes  gritty  (sandy).  Speidel  recommends  to  recal- 
jlne  it. — Polyt.  Centralbl.^  xxvil,  p.  1306. 
Volatility  of  Mercury  — Prof.  Merget  (Lyon)  has  found  that  mercury  is 
much  more  volatile  than  generally  supposed.  Instead  of  using  gold-leaf  as  test,  he 
used  a  slip  of  paper  covered  with  ammoniacal  silver-nitrate,  which  turns  quickly 
black  in  the  presence  of  mercurial  vapors.  The  result  he  arrived  at  is  :  That  mer- 
cury evaporates  even  at  its  freezing  point,  and  that  its  vapors  possess  a  great  diffusion 
power.  As  protection  to  the  workmen  in  looking-glass  factories,  he  recommends 
sprinkling  about  of  chlorinated  lime. — Jahresh.  d.  phys.  Ver.  Frank/.,  1874. 
Danger  in  Handling  Dynamit. — That  dynamit  is  not  so  very  dangerous  to 
handle,  seems  to  follow  from  the  experiments  of  Prof.  Nobel,  in  England,  A  heavy 
box  containing  dynamit  was  thrown  down  from  a  height  of  forty  feet,  it  did  not 
explode  j  neither  did  explosion  occur  by  letting  fall  a  box  with  500  pounds  of  sand 
the  same  distance  upon  some  dynamit  cartridges  5  nor  by  letting  fall  the  same  dis- 
tance 300  pounds  of  iron  upon  cartridges  and  ten  pounds  of  dynamit.  A  strong 
fire  was  lit,  and  a  box  with  50  pounds  of  dynamit  was  thrown  into  it.  It  burst  into 
a  greenish-white  flame,  but  burned  out  without  explosion.  25  pounds  of  loose  gun- 
powder were  placed  on  the  ground,  covered  with  an  iron  plate  (3-4  square  feet),  and 
on  top  of  that  were  placed  two  boxes  with  ten  pounds  of  dynamit  in  each.  By 
igniting  the  gunpowder,  the  plate  and  the  two  boxes  were  thrown  some  distance  : 
no  explosion  of  the  dynamit  occurred.  Several  dynamit  cartridges  were  placed,  to- 
gether with  some  loose  dynamit,  on  the  rails,  and  a  train  passed  over  them.  Some 
of  the  cartridges  exploded,  but  without  affecting  the  loose  dynamit. 
It  was  necessary  to  institute  such  a  series  of  experiments,  since  the  transportation 
of  dynamit  is  positively  forbidden  (for  practical  purposes,  at  least)  on  the  English 
railroads. — Burkart,  in  Oetser.  %.f.  Berg —  and  Hiitten^ivessen. 
Preservation  of  Meat. — The  following  process  has  been  patented  in  England, 
by  E,  Metge  and  F,  N.  C,  Vuibert  (France)  :  The  animal  is  killed  with  one  blow, 
and,  after  all  the  blood  is  run  out,  skinned,  and  the  intestines,  etc.,  taken  out.  The 
whole  animal  is  now  put  into  a  mixture  of  alcohol  (72  per  cent,)  with  i  per  cent, 
carbolic  acid  ;  it  is  taken  out,  and,  when  dry,  put  into  a  concentrated  alcoholic  solu- 
tion of  sugar.    It  is  now  cut  and  canned,  the  cans  being  filled  with  pure  melted  fat. 
H.  M.  W. 
