ON  METHYLATED  SPIRIT. 
151 
we  find  that  the  two  ethers  closely  resemble  each  other ;  they 
belong  to  the  same  series  of  compound  radicals,  whose  general 
formula  is  Cn  Hn  +  1,  Methyl  being  C2  H3,  Ethyl  C4  H5— and 
their  difference  is  in  the  greater  volatility  of  the  methyle,  which, 
at  a  temperature  below  zero  of  Fahrenheit,  remains  a  gas,  and 
has  resisted  a  pressure  of  20  or  30  atmospheres,  while  ethyl  is 
easily  condensed  under  the  ordinary  pressure)  and  boils  at  23° 
Fahr.  (Gregory.)  Their  ethers  in  this  respect  also  differ  widely. 
Methylic  ether  "  is  a  colorless  liquid,  of  a  peculiar  ethereal  smell, 
and  liquid  only  at  a  temperature  of  22°  to  40°."  (Regnault.) 
Ethylic  ether  is  so  well  known  that  it  need  not  be  described. 
Both  are  obtained  by  the  action  of  sulphuric  acid  on  their  respec- 
tive alcohols  ;  and  when  these  liquids  are  previously  mixed  their 
ethers  may  be  expected  to  come  ever  together,  the  one  being 
soluble  in  the  other,  and,  unless  in  so  far  as  the  greater  volatil- 
ity of  the  one  may  dispose  it  to  separate  from  the  other,  and 
thus  to  pass  into  a  state  of  gas,  that  union  may  be  permanent. 
The  extreme  difficulty  which  the  distinguished  chemists  who 
operated  on  this  subject  found  in  separating  the  two  alcohols,  and 
on  which,  indeed,  the  whole  of  the  scheme  is  founded,  renders  it 
highly  probable  that  it  will  be  no  easy  matter  to  separate  their 
ethers  from  one  another. 
As  one  means,  however,  of  determining  whether  they  are  so 
combined  in  the  ether  prepared  from  the  methylated  spirit,  the 
boiling  point  was  taken.  The  boiling  point  of  ordinary  sulphuric 
ether  is  differently  stated,  and  the  first  step  was  to  ascertain  its 
boiling  point  at  the  different  densities  of  the  Edinburgh  and 
London  Pharmacopoeias,  the  former  being  .735  at  60°  Fahr.,  the 
latter  .750 ;  the  boiling  point  then  of  the  former  was  ascertained 
to  be  96°  as  given  by  Dr.  Christison,  the  latter  98°  Fahr. 
The  boiling  point  of  ether  prepared  from  methylated  spirit  at 
these  densities  was  found  to  be  for  density,  .735  at  60°  Fahr., 
80°  ;  and  for  .750,  82°  ;  thus  showing  that  the  boiling  point  of 
the  one  is  sixteen  degrees  lower  than  that  of  the  other,  and  af- 
fording conclusive  proof  of  the  presence  of  methylic  ether. 
But  what  change  does  this  make  in  the  quality  of  the  ether  ? 
The  methylic  ether  remaining  a  gas  at  the  ordinary  temperature 
of  the  atmosphere  renders  it  impossible  to  ascertain  what  its 
properties  are  in  the  separate  state;  but  there  is  no  reason  to 
