276 
VARIETIES. 
with  marked  benefit.  The  case  is  one  of  interest,  and  we  propose  at  a 
future  time  giving  it  in  detail.  The  preparation  which  Dr.  O'Connor  uses 
is  made  by  Mr.  Bastick,  of  Brook  Street,  Grosvenor  Square. — Med.  Times 
and  Gaz.,from  Med.  News,  April,  1858. 
£No  indication  is  given  of  the  per  centage  of  strychnia  in  this  salt, 
which,  we  presume,  is  an  empirical  compound  like  citrate  of  iron  and 
quinia — as  three  grains  is  the  dose  mentioned  it  is  probable  that  the  quan- 
tity of  strychnia  it  contains  is  not  over  l-16th  of  a  grain — so  that  in  at- 
tempting to  make  the  preparation,  the  ratio  of  1  to  48  should  be  borne  in 
mind  by  the  apothecary.  We  would  suggest  the  following  formula : — Ci- 
trate of  iron,  with  excess  of  acid,  480  grains,  strychnia  10  grains,  water 
four  fluid  ounces.  Triturate  the  strychnia  with  a  portion  of  citrate  of  iron, 
and  add  it,  with  the  remainder,  to  the  water,  previously  heated  in  a  capsule, 
and  stir  till  dissolved — filter  if  necessary,  evaporate  to  a  syrupy  consist- 
ence, and  dry  on  glass. — Editor  Amer.  Jour.  Pharm.] 
Poisoning  by  Cyanide  of  Silver. — A  man  lately  drank  by  mistake,  instead 
of  water,  a  tumbler  full  of  a  solution  of  cyanide  of  silver,  from  a  large  jar 
near  which  was  standing  the  tumbler,  at  an  electrotype  establishment  in 
New  York.  Instantly  discovering  his  mistake,  a  quantity  of  lamp  oil  was 
administered,  with  a  view  to  make  him  vomit.  A  physician  was  called, 
who  administered  emetics  without  effect.  The  patient  was  then  taken  to 
the  City  Hospital,  where  he  died  shortly  after  being  admitted.  A  post- 
mortem examination  showed  that  the  lining  membrane  of  the  stomach  was 
entirely  destroyed,  and  the  brain  and  left  lung  congested.  Had  the  jar 
been  marked  "poison,"  the  fatal  mistake  would  not  probably  have  happen- 
ed.— Boston  Med.  and  Surg.  Journ.,  Feb.,  1858. 
The  Electric  Conductivity  of  Copper  Wires. Professor  W.  Thomson,  in 
measuring  the  resistance  of  wires  manufactured  for  submarine  telegraphs, 
was  surprised  to  find  differences  between  different  specimens  so  great,  as 
most  materially  to  affect  their  value  in  the  electrical  operations  for  which 
they  are  designed.  It  seemed  at  first  that  the  process  of  twisting  into  wire 
rope  and  covering  with  gutta  percha  must  be  looked  to,  to  find  the  explana- 
tion of  these  differences.  After,  however,  a  careful  examination  of  copper 
wire  strands,  some  covered,  some  uncovered,  some  varnished  with  India- 
rubber,  and  some  oxydized  by  ignition  in  a  hot  flame,  it  was  ascertained 
that  none  of  these  circumstances  produced  any  sensible  influence  on  the 
whole  resistance,  and  that  while  there  is  some  degree  of  constancy  in  the 
quality  of  wire  supplied  from  the  same  manufactory,  there  is  a  vast  supe- 
riority in  the  produce  of  some  manufactories  over  that  of  others.  A  sub- 
marine telegraph  constructed  with  copper  wire  of  one  manufactory  of  only 
1-21  of  an  inch  diameter,  covered  with  gutta  percha  to  a  diameter  of  a 
quarter  of  an  inch,  would,  with  the  same  electrical  power,  and  the  same 
