Am.  Jour.  Pliarm.) 
September,  1895.  J 
Chinquapin. 
457 
determined  as  follows  :  2-000  gms.  of  the  finely  powdered  kernels 
deprived  of  oil  were  put  into  a  pressure  bottle  with  100  c.c.  of  water, 
and  heated  for  eight  hours  at  13O-1400  C.  It  was  then  allowed  to 
cool  to  6o°  C,  and  10  c.c.  of  HC1  (sp.  gr.  1-20)  added,  and  sufficient 
water  to  make  the  bulk  100  c.c.  The  bottle  was  then  heated  at 
6o°-yo°  C.  for  two  hours.  The  contents  were  then  filtered,  neu- 
tralized and  made  up  to  500  c.c.  A  portion  was  titrated  with 
Fehling's  solution  (5  c.c.  =  0-50  glucose).  26-50  c.c.  of  chinquapin 
solution  completely  precipitated  5  c.c.  of  Fehling's  solution,  which, 
calculated,  showed  47-17  per  cent,  of  glucose.  This  was  equiva- 
lent to  44-45  per  cent,  of  starch  in  the  dried  kernels,  or  36-37  per 
cent,  on  the  fresh  kernels. 
A  nitrogen  determination  was  made  by  means  of  the  combustion 
of  rooo  gm.  of  powdered  chinquapin,  and  gave  25-2  c.c.  of  nitro- 
gen. Then  from  the  following  data  and  formula  the  per  cent,  of 
nitrogen  was  determined  : 
form  of  the  machine  they  were  indented  with  an  iron  punch  4  cm.  square  on 
its  face,  covering  the  entire  width  of  the  specimen  and  X  of  its  length  at  the 
centre.  The  results  are  different  according  to  the  direction  of  the  grain,  when, 
as  in  the  previous  illustrations,  a  pressure  of  2,395  kgms.  produces  an  indenta- 
tion of  2-54  mm.,  whereas,  when  the  grain  is  parallel  2,608  kgms.  =  4-81  mm., 
producing  a  slight  shearing  of  the  fibres.  The  following  comparative  table 
will  illustrate  the  value  of  these  figures,  and  is  taken  from  the  Tenth  United 
States  Census,  which  is  the  only  comprehensive  work  in  timber  physics  ever 
undertaken  on  American  timbers  : 
a 
verse 
gms. 
2£ 
lden- 
mm. 
-3| 
a^ 
.a 
nt  of 
n  kg 
>  tra 
th  in 
resist 
udina 
kgms 
istance  to 
tion  to  i' 
kgms. 
Species. 
Itimate 
streng 
timate 
longiti 
ing  in 
tn  03  a 
a 
P 
P 
1,658 
Larix  occidentale. 
1,141 
423 
7,923 
1,887 
Castanea  pumila. 
971 
386 
8,183 
3,388 
Ouercus  alba.  Lcana- 
856 
297 
6,106 
1,698 
Castanea  sati  va  var.  Am  eri- 
54i 
Ouercus  chrysolepis. 
13,767 
Rhizophora  mangle. 
3,395 
Asimina  triloba. 
12,689 
Canella  alba. 
