176 
VARIETIES. 
trated  by  different  roads,  into  the  central  parts  of  the  Himalaya,  Kumaon, 
and  Gurwahl ;  they  then  visited  Thibet  in  disguise,  entered  the  great  com- 
mercial station  of  Gartok,  explored  the  environs  of  Lake  Mansarowr,  and 
that  remarkable  crest  which  separates  the  waters  of  the  Indus  from  those 
of  the  Dihong,  often  erroneously  called  the  Burrampooter.  They  ascended 
the  Ibi-Gamine,  23,260  feet  in  height,  that  being  an  altitude  never  before 
attained  in  any  part  of  the  world.  After  having  been  separated  from  each 
other  for  a  space  of  fourteen  months,  during  which  M.  Robert  ascertained 
that  the  table-land  of  Amarkantak,  in  Central  India,  which  is  generally 
stated  to  be  8000  feet  above  the  level  of  the  sea,  is  not  more  than  3300  in 
height,  the  three  brothers  met  again  at  Simla,  previous  to  commencing  the 
operations  intended  for  the  summer  of  1856.  M.  Adolphus,  on  leaving  that 
place,  crossed  the  Himalaya,  when  over  Thibet,  Baltistan,  and  visited  the 
interesting  spot  where  several  mountain  crests  meet,  and  the  Hindoo  Koosh 
joins  the  range  lying  to  the  north  of  India.  He  then  returned  to  the 
Punjab  through  the  valley  of  Cashmere.  MM.  Herrmann  and  Robert  pro- 
ceeded to  Ladak  by  different  routes.  Under  good  disguises,  they  were 
enabled  to  penetrate  in  Turkistan  proper  by  crossing  the  Karakaroom  and 
the  Kuenluen  mountains,  and  descending  into  the  great  valley  of  Yarkand, 
a  region  never  visited  before,  not  even  by  Marco  Polo.  It  is  a  vast  depres- 
sion of  between  3000  and  4000  feet,  separating  the  Kuenluen  on  the  northern 
frontier  of  India  from  the  Syan-Chane,  or  mountains  of  Central  Asia,  on 
the  southern  border  of  Russia.  They  then  returned  to  Ladak,  and  entered 
the  Punjab  by  different  routes  through  Cashmere.  After  a  two  years' 
negotiation,  M.  Herrmann  was,  at  the  commencement  of  1857,  admitted  into 
Nepaul,  where  he  determined  the  altitudes  of  the  Machipoora  and  Mount 
Yassa,  which  have  hitherto  been  vaguely  called  the  Dhawalagery,  which 
means  nothing  else  but  "  snowy  crests,"  and  is  applicable  to  all  snow-capped 
mountains.  M.  Robert  proceeded  to  Bombay  through  Scinde,  Kutch,  and 
Guzerat ;  where  he  surveyed  the  chain  called  the  Salt  Range,  and  deter- 
mined the  changes  effected  in  the  course  of  centuries  in  the  course  of  several 
rivers.  Before  returning  to  Europe,  he  stayed  three  months  in  Ceylon.  M. 
Adolphus  visited  various  parts  of  the  Punjab  and  Cabulprevious  to  return- 
ing to  the  Himalaya,  where  he  still  is.  The  chief  results  obtained  from 
this  careful  exploration  of  Asia  are  the  following : — The  Himalaya  moun- 
tains everywhere  exercise  a  decided  influence  over  all  the  elements  of  the 
magnetic  force ;  the  declination  everywhere  presents  a  slight  deviation, 
causing  the  needle  to  converge  towards  the  central  part  of  that  enormous 
mass,  and  the  magnetic  intensity  is  greater  than  it  would  be  anywhere  else 
under  an  equal  latitude.  In  the  south  of  India  the  increase  of  magnetic 
intensity  from  south  to  north  is  extremely  rapid.  The  lines  of  equal  mag- 
netic intensity  have  a  remarkable  form,  similar  and  perhaps  parallel  to 
those  of  certain  groups  of  isothermal  lines.  The  three  travellers  have  col- 
lected all  the  materials  necessary  to  ascertain  this  important  fact.  Irregular 
