436  CONTRIBUTIONS    TO    ECONOMIC    GEOLOGY,  1905. 
discussion  may  be  worked  with  profit  if  connection  by  tramway  or  otherwise  is  made  with 
the  inner  side  of  the  cape,  from  which  shipments  could  be  made  by  vessel.  It  is  certain 
that  in  thickness,  quality,  and  extent  the  clays  at  Truro  outrank  any  of  the  clays  elsewhere 
exposed  on  Cape  Cod.  Occurring  as  they  do,  at  the  top  of  a  bluff,  the  pits  could  be  readily 
drained  and  the  cost  of  stripping  would  not  be  excessive,  except  in  the  region  south  of  the 
light-house,  where  the  beds,  owing  to  the  southward  dip,  are  overlain  by  a  considerable 
thickness  of  sands  and  gravel. 
Along  the  beach  from  the  point  at  which  the  clay  bed  described  disappears  little  but  sand 
is  seen  in  the  bluffs  until  a  point  about  1£  miles  northwest  of  the  Pamet  River  life-saving 
station  is  reached.  At  this  point  a  gray  to  yellowish-brown  laminated  sandy  clay  or  clayey 
sand,  associated  with  numerous  springs,  shows  above  the  beach.  It  is  much  disturbed,  and 
detached  fragments  up  to  10  feet  in  length  occur  in  lumps  upon  the  beach.  Outcrops  of 
upturned  clays,  or  possibly  large  clay  "bowlders,"  show  through  the  sands  of  the  beach 
between  high  and  low  tide  level  for  some  distance.  The  material  seems  to  represent  the 
transition  between  the  Gardiner  clay  and  the  Jacob  sands.  One-fourth  mile  farther  south 
a  few  feet  of  very  fine,  compact,  and  somewhat  contorted  sandy  clay  of  a  greenish  color, 
interlaminated  with  sand,  were  seen.  This  clayey  sand  or  sandy  clay  continues  to  show 
along  the  beach  southward  for  about  one-eighth  mile,  when  it  again  disappears  beneath  the 
beach,  only  to  reappear  for  a  short  distance  about  half  a  mile  farther  on,  or  three-fourths  of  a 
mile  from  the  life-saving  station.  The  material  does  not  belong  to  the  Gardiner  clay,  but 
rather  to  the  Jacob  sands,  and,  although  some  portions  may  contain  a  sufficient  amount  of 
true  clay  for  the  material  to  be  utilized  for  briekmaking,  very  little  of  the  deposit  as  a  whole 
could  be  so  used. 
In  front  of  the  life-saving  station  a  greenish  and  olive  clay,  full  of  iron  lamina?  and  con- 
cretions, outcrops  in  the  beach  between  high  and  low  tide  mark.  It  seems  most  probable 
that  it  is  associated  with  the  peat  which  is  being  undermined  by  the  waves  as  they  cut  back 
into  the  extension  of  Pamet  River  Valley  and  that  it  is  of  post-Wisconsin  origin. 
No  complete  traverse  of  the  west  coast  of  the  Truro  district  was  made.  The  gray  to 
orange  sandy  clay,  however,  was  seen  in  the  bluff  about  a  mile  northwest  of  North  Truro, 
but  the  bed  was  only  about  2  feet  thick.  Some  sandy  clays  or  clayey  sands  were  also  seen 
in  the  bluffs  2  miles  south  of  North  Truro.  Neither  of  these  clays  will  prove  of  economic 
value  unless  it  is  for  use  on  roads  or  other  local  purposes. 
Wellfleet  region. — This  region  includes  the  high  rolling  land  from  South  Wellfleet  north- 
ward to  Pamet  River,  in  the  southern  part  of  Truro  Township.  In  the  work  in  this  district 
the  beaches  on  both  the  ocean  and  the  bay  side  were  traversed  and  all  localities  which 
inquiry  showed  to  contain  clays  were  visited. 
Southward  along  the  coast  from  the  Pamet  River  life-saving  station  clays  are  first  exposed 
in  the  bluff  about  one-fourth  mile  distant,  where  a  few  feet  of  clay  project  through  the  talus 
at  a  single  point.  The  clay  shows  again  about  one-half  mile  south  of  the  station,  but  it  is 
not  until  a  point  1?  miles  south  is  reached  that  the  clay  is  seen  in  any  considerable  amounts. 
Here,  however,  nearly  20  feet  of  clay  are  exposed  along  the  bluff  for  some  distance.  It  is 
of  the  dark  blue-gray  type  characteristic  of  the  Gardiner  clay,  but  has  thin  layers  of  yellow- 
ish sand.  It  seems  to  be  moderately  folded  and  is  overlain  by  20  to  30  feet  of  stratified  sand 
and  gravel.  A  few  hundred  feet  farther  on  the  clay  dips  nearly  or  quite  to  beach  level,  but 
soon  rises  again  and  is  seen  through  the  talus  at  scattered  points  for  about  one-fourth  mile, 
beyond  which  it  is  again  well  exposed  as  a  horizontal  bed  20  feet  thick  at  the  bottom  of  the 
bluff  at  numerous  points  for  another  half  mile,  south  of  which  it  is  covered  by  talus.  It 
appears  to  sink  below  the  level  of  the  sea  at  a  point  northeast  of  Long  Pond,  but  is  strongly 
developed  again  one-half  mile  farther  south,  where  it  occurs  as  a  strongly  folded  bed  over- 
lain by  from  10  to  30  feet  of  sands  and  gravels.  South  of  this  point  talus  prevents  the  clay 
from  being  seen;  it  probably,  however,  sinks  rapidly  and  goes  below  sea  level,  not  reap- 
pearing anywhere  north  of  South  Wellfleet.  In  addition  to  the  Gardiner  clay  there  are  a 
number  of  thin  beds  of  sandy  clay  a  foot  or  two  in  thickness  interstratified  with  the  sands 
and  gravels  constituting  the  bluffs. 
