A preliminary investigation of a submerged electrode for quantitative spectroscopic analysis
by Douglas N Stewart
A THESIS Submitted to the Graduate Committee in partial fulfillment of the requirements for the
degree of Master of Science in Chemistry
Montana State University
© Copyright by Douglas N Stewart (1949)
Abstract:
The possibility of using submerged 60 cycle alternating current electrodes as a light source for
quantitative Chemical analyst was investigated. The Intensities of the spectral lines produced were
measured hy means of a multiplier phototube. The studies were made using the internal standard
method. A series of teste were made with lithium as the Internal standard and adding Mg, Ca, Zn and
Cu in varying amounts.
A series of tests were also made using cadmium as the internal standard and adding Li, Mg, Ce, Zn end
Cu In varying amounts. A PBBLIMISAai XaVSSftoAflOS Op A SUHMStoBD KLaCTROLZ
JfOR Q^AJfTITATITE SPECTROSCOPIC ASALXSlS
By
DOWLAS N. STKfifAST
A THSSIS
S rib a itte d to th e S re d u s te Committee
la
p a r t i a l f u l f i l l m e n t o f th e req u irem en t*
f o r th e d eg ree o f
M aster o f S elenee In C h e a le try
el
Montana S ta te C o lleg e
Approved*
H e ad .^ A jo r D epartm ent
-T-:------- r - — . .
B oteaan, Montana
J u ly 19U9
5 + a ^ \
Ctr ji ^ •
TABLS S t C O Jim M
Pg.
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....................................................................................
IX,
ISTSOUUCf............................................................
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14
V. o s a w l CuasIBEBl-tlOS Of THS BATA . .
V I. DATA. . . . .
VII.
15
................................................
38
B lS C U S S IO S .........................* .....................
42
V I I I . .... .......... ...................................................................
&3
IX. ACEftOVLSDOMIST. ................................... .... ‘
9 2 5 5 ^
2
I*
ABSTRACT
The p o s s i b i l i t y o f u s in g submerged 60 c y c le s l t e r a s t l & f c u rre n t
e le c tr o d e s ee e l i g h t source f o r q u s a tI t s t I r e c h e a lc s l B n ely ele wee In v e e tl g s te d .
The I n t e n s i t i e s o f th e s p e e tr e l l i n e s produced w ere a e ssu re d
by raepne o f e m u l t i p l i e r p h o to tu b e .
l n t e m e l e te n d e rd m ethod.
The s tu d ie s were me.de u s in g th e
A s e r i e s o f t e s t s were aede w ith lith iu m $s
th e I n t e m e l stB nderd and adding % , Ce, Zn »nd Cu in v a ry in g m o u n ts .
A s e r i e s o f t e s t s w ere e ls e m#de u s in g eedmiua re th e in te r n e I stan d ard
and adding L i, Mg, Ce, Zn end Cu In v a ry in g am ounts.
- 3 -
II.
IMTBODuCTIOK
The submerged e le c tr o d e u sed In t h l a etudy we* f i r s t In v e e ti^ e te d by
fe d d 1 .
He need i t f o r q u e l i t e t l v e d e te rm in a tio n s .
A l i s t o f th e e le n e n te
end th e lo w er l i m i t s o f c o n c e n tre t lone t h s t cen be d e te c te d v l e u s l l y wee
given by him .
D uring p re v io u s work e t t h i s i n s t i t u t i o n some ehenges hed been mad#
in th e e p p e re tu s su g g este d by Todd,
from th o se changes end o b s e rv a tio n s
i t was th o u g h t t h a t f u r t h e r in v e s t ig a ti o n o f th e r e l a t i o n betw een concen­
t r a t i o n and i n t e n s i t i e s o f th e e p e c tr e l l i n e s produced, m ight r e s u l t in e
q u a n t i t a t i v e method o f a n a ly s is o f s o lu tio n s .
W ith th e p o s s i b i l i t y o f a method f o r q u a n t i t a t i v e d e te rm in a tio n o f
elem en ts In s o lu tio n s in mind, i t was d e cid e d to c o n s tr u c t th e n ecessary
a p p a ra tu s needed to o p e ra te # m u l t i p l i e r p h o to tu b e , end e p re lim in a ry
stu d y o f th e e f f e c t s o f a d d itio n a l elem en ts i n th e s o lu tio n s was a ls o to
be made I f th e I n t e n s i t y o f th e l i g h t so u rce was found to be ad eq u ate.
I t he# Io n s been re c o g n ise d t h a t e l i g h t so u rce c a p a b le o f g iv in g #
homogeneous l i g h t f o r e c o n s id e ra b le le n g th o f tim e would in c re a s e the
u s e f u ln e s s o f th e s p e c tro s c o p e .
The p o s s i b i l i t y o f o b ta in in g a d d itio n a l in fo rm a tio n on th e b e h av io r
o f io n s In s o lu tio n was re co g n ized in p la n n in g t h i s s tu d y .
I
J . Cheo.
V 15, p 241 (1938)
4 -
A - In p u t A. C. v o lta g e r e g u la to r
B - D. C. Power supply to p h o to m u ltip lie r
tube
C - P h o to m u ltip lie r Tube
D - A m p lifier to galvanom eter
E - G alvanom eter
E - Spectroscope
G - Submerged e le c tro d e
H - C o n tro l p a n el f o r submerged e le c tro d e
Arrangement o f In stru m e n ts
F ig u re I
m .
m m m
Input Constant Voltmae Sqgulmt o r ;
The le r g e d a l l y f lu c t u a t i o n s o f l i n e v o lta g e and amperage made I t
n e c e s s a ry to s t a b i l i z e th e pow er so u rce f o r b o th th e d i r e c t c u r r e n t power
su p p ly and th e a l t e r n a t i n g c u r r e n t su p p ly to th e submerged e le c tr o d e s .
Any change In th e d , e . v o lta g e su p p lie d to th e m u l t i p l i e r p h o to tu b e would
have changed th e a m p lif ic a tio n f a c t o r o f th e tu b e .
To check th e v o lta g e
r e g u l a t o r , a v a r ia b le tra n s fo rm e r wee p la c e d in th e supply l i n e to th e
v o lta g e r e g u la to r ,
f o r a 10 v o l t change in th e v a r ia b le tra n s fo rm e r no
change in th e o u tp u t v o lta g e o f th e d . c , power supply c o u ld be d e te c te d
w ith e 7- in ch T r i p l e t t v o lt- o h s w a lllle m ie te r , 50,990 o h m s/v o lt d . c .
D ire c t CtoTftBt HfiltflX HHfflglX»
The power su p p ly , f ig u r e 2 , c o n s is te d o f a h ig h -v o lta g e tra n s fo rm e r,
*2 , 1509- 9-1509 v o l t s , 115 v o lte p rim ary ; two h alf-w av e m ercury r e c t i f i e r
tu b e s , RCA 8l 6 ; # f i l t e r i n g system o f two c o n d e n se rs, C^, Cg , h
a u r-f,
3000
v o l t e d . c . i two ch o k es, L1, Lg , 12 h e a e ry s , 80 me. d . c . j end a bank o f
v o lta g e r e g u la to r tu b e s , RCA V890, to se rv e a s a v o lta g e d i v i d e r f o r th e
m u l t i p l i e r p h o to tu b e .
A 190,909 ohms, 30 w a tt r e s i s t o r , R j1 served a s e
a san e o f d is c h a rg in g th e co n d en sers when th e power supply was tu rn ed o f f .
A s i m i l a r power supply wee u sed by Dleke and C ro ssw h ite 1 .
M u ltip lie r m & totw bft:
The m u l t i p l i e r p h o to tu b e u sed w ith t h i s work was a RCA IP 22 having
# s p e c t r a l re sp o n se o f about **000 A0 to 7000 A0 .
1
J . O pt. Soc. o f Am.
7 35, p **71 (1985)
-
6
-
H Is c a p a b le o f a u l t t -
R2 10, OOO-a .
VR 105
0-50 ma'
RCA 816
RCA 816
D ir e c t C u rren t Power Supply
VR 90
p ly in g f e e b le c u r r e n ts produced u n d e r week l l l u a l n e t l o n by an everege
v e lu e o f 200*000 tim e* when o p e ra te d »1 100 v o l t s p e r s ta g e .
A good review
on th e b e h a v io r o f » m u l t i p l i e r tu b e Ie g iv e n by E ngetroa1 ,
The e h e r e o te r-
l e t l c e o f th e tu b e I t s e l f a re p re s e n te d In t e n t a t i v e d a ta p u b lis h e d by
2
RCA .
An e le c tr o n m u l t i p l i e r Ie e vacuum tu b e In which th e e le c tr o n s
e m itte d from th e Illu m in a te d cath o d e a re d ir e c te d by fix e d e l e c t r o s t a t i c
f i e l d s to th e f i r s t dynode (se co n d a ry e m i t t e r ) .
The e le c tr o n s Im pinging
on th e dynode s u rfa c e produce many o th e r e l e c t r o n s .
These secondary
e le c tr o n s a re d ir e c te d to s second dynode end th e s e produce many more
e le c tro n s .
T h is p ro c e s s Is re p e a te d u n t i l th e f i n a l sta g e i s reached
where th e y a re c o lle c te d and c o n s t i t u t e th e c u r r e n t u t i l i s e d In th e ou t­
p u t c u r r e n t.
A m p lifie r. % 9tQ .taM JtO. f a lrr a p a ftts E t
The a m p lif ie r tu b e was a RGA 959^ aco rn ty p e tube w ire d a# a reduced
g r i d c u r r e n t tu b e In which Sg i s th e space ch arg e g rid (s c re e n ) end
th e c o n tr o l g r id .
The c i r c u i t in which I t was u sed was a B ubridge and
Brown5* b a lan c e d c i r c u i t .
in g c o n d itio n s .
Only s l i g h t changes were made to f i t th e e x i s t ­
A 70 meg.^ r e s i s t o r was u sed a s th e g r id b i a s r e s i s t o r .
The v o lta g e s need on th e 959 tu b e w ere f ila m e n t ,6 5 v o l t s , p l a t e and
s c re e n 6 v o lte e a c h .
1
2
/
%
5
A fte r th e i n s t a l l a t i o n was com pleted th e c i r c u i t
J . O pt. Soe. o f Am. V 77, p *20 (19*7)
RCA V ic to r D iv is io n , Radio C o rp o ra tio n o f America
RSI V 18. p 16 (19b?)
RSI V * , p 532 (1913)
S . S. W hite D e n ta l Mfg. Co.
w8 —
th e c i r c u i t wee h e le n c e d ns reeoaaended "by PuhrM ge sad Browa *
3 , I g was s e t s t 25 o M e,
I a f ig u r e
s d ju e te d to g iv e th e d e s ir e d f ll s m e a t v o lts g e
^nd R th e d e s ir e d p i s t e ra d s c re e n v o lte g # . B7 d e c re a se d th e a e s le re e d k
la g hy 5 tim e s , % A djusted th e p o s itio n o f th e g slv sn o m e te r re s d la g on
I t s e e rie .
Hoto tu b e .
The le n d w ire "A* wee from th e sao d e, Ifo, 10# o f th e m u l t i p l i e r
Lend *3*. th e r e t u r n w ire , to th e d . c . power su p p ly .
Rubaar^efi E le c tro d e s rad P o a t r o l a t
The submerged e le c tr o d e s , f ig u r e 4 , c o n s is te d o f e s h o r t p i n t Inua
w ire pad a lo n g e r o n e.
When th e system wee tu rn e d on e s p u tte r in g glow
Pppe e re d on th e s h o r te r e le c tr o d e ,
th e l i g h t from th e s h o r t e le c tro d e
i s th e l i g h t so u rc e t h a t I s u sed w ith th e s p e c tro s c o p e .
I t I s presumed
t h a t th e l i g h t produced Is from th e b u m la g o f th e oxygen end hydrogen
g en erate d by th e a l t e r n a t i n g c y c le s o f th e s . c* used on th e e le c tro d e s
and th e m e ta llic Io a b e in g c a r r ie d In to th e flam e by th e c u r r e n t.
The c o n tr o l to th e e le c tr o d e s wee a r e s i s t o r l a s e r i e s w ith I t ,
Its
p u rp o se Was to a d ju s t th e amperage drawn by th e e le c tr o d e s to th e d e s ir e d
v a lu e .
!S I
V U1 p 532 (1933)
- 9 —
4
hB^70meg
A /v ^ A Z —
R0 50 -TL.
R3 200
12 v
F igu re 3
A m p lifie r , M u lt ip lie r Phototube to Oalvsnom eter
RU 100.
©
< _ y
1
v o lts J
HO v .
/ - J L
Submerged
E le c tr o d e s
v
R1 ; 125-n . 500 v
R2 ; 7 5 -n- 300 w
y
F igu re 4
Submerged E le c tr o d e s and C o n tro ls
jv ,
axyasiw & x?*! gEC-cssm^s
Th* fo llo w in g c o n d itio n s *nd p ro c e d u re s were fo llo w e d f o r th e r e r io u e
p ie c e s o f equipm ent f o r e l l t e s t s th e t were a e d e .
B isy pro n o t in chrono­
lo g ic a l o rd e r*
1.
A ll power need wee drewn thro u g h th e e o n e te a t v o lta g e tra n s fo rm e r.
2.
She ra p e rrg e s u p p lie d to th e h sak o f V. R* tu b e s o f th e d . c . power
su pply wee 23 me.
3.
The v o lte g e s o f th e 959 tube w ere, f ils m e n t .65 v o l t e , p l a t e end
s c re e n 6 v o l t s e a c h ,
U.
The r e s is ta n c e R0 , f ig u r e 3 , wee s e t a t o n e -h e lf o f I t e r a te d v a lu e .
5.
The 12 v o l t b a t t e r y was rech arg ed a f t e r each 10-12 h o u rs o f u s e .
6.
The d . e . power su p p ly end a m p lif ie r w ere given e 3 hour warm up
p e rio d b e fo re any t e s t s were a e d e .
7.
The 959 tube wet k e p t s h ie ld e d from l i g h t end e l l p ie c e s o f equipment
w ere grounded end s h ie ld e d s t e l l tim e s .
8.
Twenty a l o f s o lu tio n were u sed w ith th e submerged e le c tro d e *
9.
One cm o f th e s h o r t e le c tr o d e wee submerged when re a d in g s were b e in g
ta k e n .
10. The te m p e ra tu re o f th e s o lu tio n b e in g te s te d m ust be allow ed to re a ch
• e q u ilib riu m w ith th e c o o lin g w a te r b e fo re any re a d in g s e re ta k e n .
U.
The e e t t l n g o f th e in t e r n a l s ta n d a rd was 250 cm on th e galvanom eter
s c a le .
The amperage n e c e ssa ry to g iv e t h i s d e f l e c t i o n wee o b ta in e d
by a d ju s tin g th e r e s i s t a n c e in s e r i e s w ith th e e le c tr o d e s .
12. When i g n i t i n g th e e le c tr o d e , th e l e s s th e s h o rt e le c tr o d e I s submerged,
th e le a * th e p o s s i b i l i t y o f th e b u rn in g o f f o f th e t i p o f th e e le c tr o d e .
- 12 -
>.e soon Sg p o s s ib le a f t e r th e e le c tr o d e had beaa I g n ite d , th e e le c ­
tro d e wag submerged to th e d e s ir e d d e p th end th e r e e ls te n c # la s e r i e s
v l t h I t was In c re a s e d u n t i l th e e le c tr o d e hed l o s t I t s re d -h o t c o lo r .
The eeperege to th e e le c tr o d e was l a t e r a d ju s te d to th e d e s ir e d v a lu e
a f t e r th e I t ;h t source had b een p la c e d In lin e w ith th e o p tic a l
s y e te a o f th e e tse c tro sco p e.
13.
The f i n a l t e s t s o lu tio n s were h S w ith r e s p e c t to n i t r i c a c id .
14.
The fo llo w in g l i n e s were u sed in t ek in g th e re e d in g si
15.
L ithium
6708 A0
Cadmium
5086 A0
Copper
5218 A0
Zinc
4722 A°
Magnesium
5184 A°
Calcium
4226 A0
The c o n tin u o u s l i # t spectruza, background l i g h t , p ro duced by th e h o t
e le c tr o d e , wee s u b tra c te d from th e av erag e maximum d e f le c ti o n o f th e
$*Iv e n e a e te r re a d in g l a b e l l e d " d if f e r e n c e " In th e t a b l e s .
16.
In o rd e r to o b ta in th e av erag e maximum d e f le c ti o n re e d in g o f th e
g alvanom eter e c e le , i t was n e c e s sa ry to c o n s id e r th e le n g th o f tim e
th e l i g h t beam from th e galvanom eter s p e n t e t a given s e t t i n g , i . e .
10 seconds a t 265 cm would be more im p o rta n t th a n *1 second a t 2?9
cm.
The s p u tte r in g o f th e e le c tr o d e caused th e g alv an o m eter to be
u n s ta b le .
17.
The fo llo w in g s ta n d a rd s o lu tio n s w ere made from th e w eig h ed -o u t s to c k
s o lu tio n s o f .1 0 n tg/alt
e lem en t.
5» »5« . 05« 2 , . 2 , . 02, I , ,1 ag/ral o f each
% e s ta n d a rd s o lu tio n s were In tu rn u sed to make th e fo llo w ­
ing c o n c e n tra tio n s when made up w ith th e 20 ml o f th e HMO^ u sed on
th e e le c tr o d e s ! . 5 , . 25, . 1, . 05, . 025» .0 1 mg/ml o f each elem ent.
« 13
I.
m m ii
jg g n m
Ia eay 20 ml o f s o lu tio n th e c o n c e n tra tio n s o f th e e le a e n te p r e s e n t
were th e eeae ex cep t f o r th e I n te r n a l s ta n d s rd s which wee »2 a g / a l l a s l l
Ceeeet w heress th e lith iu m o f Tmblee I I th ro u g h V end th e co p p er In Table
X IIt b o th o f which w ere f iv e tim es th e c o n c e n tre t Ion o f th e o th e r s .
It
was n o t p o e e lb le to d e t e c t th e l l t h l i a end co p p er In th e sane c o n c e n tra ­
tio n me th e o th e r elem ents*
The graph* o f th e d*t«- were -ro u p ed ♦
T lp ire s 5 th ro u g h 9 a re th o se
in which cmdalua wme u sed me th e I n te r n a l s ta n d a rd .
T lg u ree 10 through
13 a re th o s e w ith lith iu m as th e I n te r n a l s ta n d a rd .
Imch f ig u r e Ie «t p l o t
o f a s in g le elem en t.
The Bommn num erals t h a t id e n tif y e re h curve a lso
r e p r e s e n t th e ta b le from which th e d a te f o r th e cu rv e was o b ta in e d .
The
legend on each graph g iv e s f I r e t t th e elem en t used es th e in te r n a l standard*
second, th e elem ent p l o t t e d i s u n d e rlin e d * t h i r d , any a d d itio n a l elem en ts
th a t w ere p r e s e n t In th e same s o lu tio n .
The amperages a p p ea rin g in T igure
Ih were th e am perages r e q u ire d by th e i n t e r n a l s ta n d a rd in o rd e r to
produce a d e f le c ti o n o f 250 cm on th e g alvanom eter s c a le .
O
Galvanometer
Zero
O
M
M
h»
Rl
§
kS
)$
kS
&
h
h
^
£
t
^
§
S
a
*
"
#
a
#
^
til
^
*
'O
Vt
O
Hi
H
M
g - - S i e
O
VR
O
9_
H
Rl
tr
vn
VR
VIt
O
Vt
*
3
*
§
#
3
3
3
t-*
H
^
S
01
M
3
e
*
H
O
Ht
H<
S
A verage
Maximum
D e f le c tio n
D iffe r e n c e
mg/ml
Background
L ight
0»
Vt
3
Vt
Rl
$
M
a
XA
Rl
s
Jl
I
t*
*■*
Average
Maximum
•
Vl
•
Rl
-Q
•
Rl
Vt
•
Vl
N
s
a
a
a
y
a
«
s
•
*
*
•
O
P-
Amperage
A pp lied to
Rl
E le c tro d e s
«8
V oltage
A cross
E le c tr o d e s
Ohms in
S e r ie s w ith
E le c tr o d e s
&
mg/ml
XA
no
Xa
H*
s
to
O
a
<i
Xa
M
a
O
H
s
Background
L igh t
d?
Average
Maximum
D e fle c tio n
S1
D iffe r e n c e
3
3
3
mg/ml
Background
Light
Average
Maximum
D e f le c t io n
Average
Maximum
D iffe r e n c e
D iffe r e n c e
•
M
VM
Rl
mg/ml
Background
L ight
M
»
XJX
Galvanometer
Zero
D e fle c tio n
Reading* o f L i, Mg; Cd I n te r n a l S tan d ard
$
VA
2
TABLE I I .
k
Average
Maximum
M e f le c t inn
Amperage
A pplied to
IT,I eetrrwiea
V oltage
A cross
E le c tr o d e s
Ohms in
S e r ie s w ith
E le c tr o d e s
H
O
D e fle c t!o n
'% xt€VS
O
pjap iw iS la tw e tu i po :% j o eS u ip eea
O
m
TA llS I I I .
Re*dIage o f 11, Hg, Cu; Cd I n t e r a s l S tsnderd
O 03
1O
> O
H k
Cd 4>
® H
C
80 k
t
OUr-C
t* «S W
-«! S P
O SO
0)
<Di-l
® K <H
>
a)
e K s-
03
* C ontinued on n e x t pe&e
*
TAILS I ? .
Resdin=:* o f 1 1 , Mg, Zn, Ce; Cd I n te r n e ! Stendard
Li
D iffe re n c e
mg/ml
250
*^3
96
36
.5
20
200
180
.1
3
250
.3 3
94
49
.25
25
200
175
.0 5
65
290
225
C
250
.2 9
96
4?
.1
25
120
95
.0 2 5
70
180
HO
O
250
.2 4
96
4?
.0 3
30
85
55
.0 1
70
100
30
♦Continued on n e x t page
16
D iffe re n c e
Average
Maximum
D e fle c tio n
Background
L ight
Background
L ight
O
Average
Maximum
D e fle c tio n
0 a
40 a
0) X
Sfl Xj C
KUf h -H *:
Q> iH C
P P I
mg/ml
V oltage
A cross
E le c tro d e s
Ohms in
S e rie s w ith
E le c tro d e s __
Hg
Average
Maximum
D e fle c tio n __
G alvanom eter
Zero
GeI .2 ng/m l
0: f see Le
S
mg/ml
£
3
Background
L ight
3
S
I
D iffe r e n c e
+
*
*
O
O
H
M
VA
V%
10
10
IU
12
s
at
s
I
9
«
«r
8
8
3
m
ex
o
UX
•
"
mg/ml
VA
Background
Light
Average
Maximum
D e fle c tio n
O
3
3
5
8
O
»
4
Ux
D iffe r e n c e
mg/ml
mg/ml
6
21
55
170
Background
L ight
Average
Maximum
p efI a c t i o n
•
Cl
9
Background
L ight
Average
Maximum
D e fle c tio n
D iffe r e n c e
D iffe r e n c e
mg/ml
mg/ml
Background
L ight
Background
Light
Average
Maximum
Ttefl Act.!on
Average
Maximum
D iffe r e n c e
D iffe r e n c e
B efl Afition
Continued
170
Average
Maximum
B e f l e c t i on
Contim ied
110
#
O
H
•
•
H
Ux
85
»
O
TABLE I I I ,
•
O
M
Ux
SAILS IV,
♦
O
H
#
t U t ! V.
SeeA iage o f L i, Cu, Mg, Zn, Cr ; Cd I n t o r a e l S teM erd
Cu
mg/ml
Background
L ight
250
.5
100
24
•5
60
199
130
.1
70
150
80
10
2&>
*32
97
62
.2 5
40
190
150
.0 5
85
120
35
3
250
,28
94
53
.1
34
125
91
.025
78
HO
32
5
250
.29
95
.OJ
40
95
55
.0 1
84
112
28
•C o a tlnusd on n e x t pege
tASIS V I.
!> p
r—
I 9-i
Cd to
«rHr-
O
W
• ti
C
<U H
H eedlnge o f % , Ce; Cd I n te r n e ! S ten d erd
t
>
> -e H
- 18-
Cd to
JSd 43
O W
)
<6 Ti
PP i-P
<U K <h
D iffe re n c e
D iffe re n c e
O
III
mg/ml
Uii
*4 "H r0) H tn
555
Average
Maximum
D e fle c tio n
Average
Maximum
C
Background
L ig h t
O 03
03
0) rO
Mod 0
CDo0)
Jh
H -P
Q) c-l C
Li
V oltage
A cross
E le c tro d e s
Ohms in
S e rie s w ith
E le c tro d e s
G alvanom eter
Zero
Cd ,2 BJg/» 1
*
*
#
mg/ml
VX
CR
Average
Maximum
R e f le c t io n
M
K
a
D iffe r e n c e
«
S
•
*
»
•
^
mg/ml
Background
L ight
Average
Maximum
D e f le o t io n
s
1S
a
g
Background
Light
a
s
D iffe r e n c e
K
a
mg/ml
S
Sx
V
S
M
mg/ml
^
^
8
Vx
Background
Light
Average
Maximum
mg/ml
Background
L ight
Average
Maximum
D e f len tln n
D iffe r e n c e
eo
m
Vx
O
O
S
s
V
Average
Maximum
D e fle c tio n
s
S
8VX
a
D iffe r e n c e
S
S
a
Background
Light
s
S
Average
Maximum
D e fle c tio n
6»
D iffe r e n c e
J
#
3
3
Ox
5
tS
S
DeflAotion
D iffe r e n c e
O
9»
C ontinued
Background
L ight
M
TABlB V.
*
mg/ml
S eeding* o f Mg, Zn, Ce; Cd I n t e m s l StendePd
Za
Background
L ight
20
190
170
225
.0 5
UO
112
72
160
90
.025
55
70
15
100
30
.01
45
65
25
250
.U l
89
53
.1
5
255
,32
90
57
.05
65
290
5
235
.27
96
47
.025
70
5
250
.27
96
49
,01
70
0; 'f see
Le
D iffe re n c e
mg/ml
C
C
,1
O
D iffe re n c e
mg/ml
Background
L ig h t
Hs
Average
Maximum
D e fle c tio n
Amperage
A pplied to
JS lectro d es
V oltage
A cross
E le c tro d e s
Ohms in
S e rie s w ith
E le c tro d e s
G alvanom eter
Zero
CiI ,2 m.g/ffll
Average
Maximum
JD fiflection
TH.
e a
ijp 3 t
ro S a
F -P -H rfl) K «H
-Ss p
wC o n tin u e i on n e x t pejge
*
fABLS ? I I I ,
B endlage o f Ca* Mg, Zn* Ce; Cd I n t e r n a l Stenderd
CiI .2 mg/ml
<D
■4—
*
C
a
Of-
P -
H £
Cb N
Cu
so
rO
0 <r
Q) rG
STS
S
eH
Mg
a
c
+3 O
ti
I
nH CO
Q) -P
| ! i
* Sti
g 8 V | g ; j H h a) ^ F-P a
^ s f ■«! -S’ pi >- <! H O OT S
H
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S
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s
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MB 0
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<S A
A
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5
255
.36
89
57
.1
45
75
30
.1
5
255
.3 4
91
53
,05
65
95
30
.0 5
60
285
225
0
250
.31
95
46
,325
70
105
35
.025
79
155
85
5
260
•31
96
43
.01
85
HO
25
.01
75
105
30
•C ontinued on n e x t peg#
20
oi f BOft- .e
mg/ml
Average
Maximum
R e f le c t io n
D iffe r e n c e
H
O
vjJ
fO
-4
Ul
06H
U%
s
s
Ut
a
"h
8
a
S
3
ot
8
y
5
Tl
L
8
Cl
3
M
Ul
O
Ul
mg/ml
Background
Light
%
a
a
a
Average
Maximum
D e fle c tio n
»
S
S
S
D iffe r e n c e
mg/ml
Background
L ight
Average
Maximum
p efI A ctio n
H
mg/ml
Background
Light
O
»
•
Average
Maximum
D e fle c tio n
D iffe r e n c e
D iffe r e n c e
mg/ml
mg/ ml
Background
L ight
Background
L ight
Average
Maximum
R e fle r tln n
Average
Maximum
D iffe r e n c e
D iffe r e n c e
R e fle c tio n
Cl
C ontinued
N»
S
H
S
C ontinued
t
O
5
^
BackgroundL ight
O
H
IT
^
H
TABLE T i l ,
Ut
17
g
O
5
^
O
«
TABLB T t H .
O
H
•
^
*
PO
>u»
*
W
M
^
S'
101
101
102
102
V#
Vx
v*
-<l
1M
V
Mx
V
O
H
O
N
VX
S
Vx
K
78
H
ox
M
Amperage
A pplied to
Hll e e t r n d e e
V oltage
A cross
E le c tro d e s
Ohms in
S e rie s w ith
mg/ml
S
Background
L ight
H
o'-a
t*
*•»
h>
&
>
H
E le o tro d e e
H
220
37
20
c»
g
O
D e f I e f it I o n
Average
Maximum
D e fle c tio n
D iffe re n c e
mg/ml
H
M
VX
I
I
S
3
W
^
^
k
H
H
S
S
H
S
S
cs
g
a
at
S
§
VX
S
""
S
3
S
^
8
M
"d
O
S’
Vx
CS
O
Galvanometer
Zero
Average
Maximum
D efle n t i on
Amperage
A pplied to
B Ieo tro d es
V oltage
A cross
E le c tro d e s
Ohms in
S e rie s w ith
E le c tro d e s
t**
M
h*
I
mg/ml
Background
L ight
5
~
$
Average
Maximum
D e fle c tio n
H
®
D iffe re n c e
mg/ml
Background
L ight
Background
Light
Average
Maximum
D e fle c tio n
Average
Maximum
D e fle c t!o n
D iffe re n c e
D ifferen ce
'%%
»
f*
VX
1S
Average
Maximum
VX
*#K j o a5uip«#%
is
H
O
2
H
is
M
G alvanom eter
Zero
putepw^s
M
O
*y ErIgVS
M
O
r»b JO «£tr|p«»g
V*
pjupudn* istu e » u i n
vu»
\*
O
M
M
M
h»
S
1S
S
1S
h
I
g
W
->»
W
VA
•
•
W
3
2
O
VA
H
S
M
S
v
h
S
W
3
f
H
W
Average
Maximum
T le f l e e t i nn
Amperage
A pplied to
•
•
VA
mg/ml
3
%
Background
L ight
N
VA
H
Average
Maximum
D e f le c t io n
W
3
3
D iffe r e n c e
mg/ml
03
f
»e
Te
»♦
1S
ill ee t.rr w lee
V oltage
A cross
E le c tr o d e s
Ohms in
S e r ie s w ith
E le ctro d e s
O
$
O
w
S
IS
S
I
g,
g
TABlS XII ♦ R erd tn g o f Gut L i I n t e m e l E trn d p rd
k
Galvanometer
Zero
f
i»
E
i
3
\5
*
O
M
•
O
M
2
3
CD
s
s
%
O
^
3
Galvanometer
Zero
Average
Maximum
D e fle c tio n
Amperage
A p p lied to
E le c tr o d e s
V oltage
A cross
E le c tr o d e s
Ohms in
S e r ie s w ith
E le c tr o d e s
•
*
H
VA
mg/ml
3
3
Background
L igh t
Average
Maximum
D e f le c tio n
S
2
5
1S
VA
K
3
3
D iffe r e n c e
mg/ml
Background
L ight
Background
Light
Average
Maximum
D e f le c tio n
Average
Maximum
D e fle c t!o n
D iffe r e n c e
D iffe r e n c e
Ir*
M
S
%
H
Sf
'IX SfXffVi
O
Idujte^ui v i tng j o Baypaeg
<A
TABUB XZ11«
o o>
T-t 0)
<D4^
B C
S e e d ittfe o f Mg, Zn, Ge; Li Ia te rn m l S tead erd
5
255
6
260
O
250
3
255
ee e l >
99
29
*1
99
30
.05
90
305
215
.05
55
175
.31
100
22
.025
80
165
85
.025
55
85
30
.36
100
27
.01
75
105
30
.0 1
55
68
13
.5
•C oat lmied on n e x t peg#
of:
- 24 -
.1
D iffe r e n c e
Za
Average
Maximum
D e f le c t io n
Hs
Background
L ight
a)
®
O
a
X
C
JHC
mg/ml
O
hj
Mg
V oltage
A cross
E le c tr o d e s
Ohms in
S e r ie s w ith
E le c tr o d e s __
Average
Maximum
D e f le c tio n __
Galvanometer
Zero
LiL .2 ag/m l
CU
M 1O
Cd
Jh h-H
r-H
O M) ® K V
Background
L ight
TASLB XIT.*
Jh «H rH
O W)
®H
OMM
mg/ml
P
E P.
D iffe r e n c e
« S
H Jh ®
Average
Maximum
D e f le c t io n
> O
o) ®
IWmdla g # o f Hf* Ge; Li I n t e r a e l S te a d erd
Ofi SOeli i
120
O
H
•
O
M
VA
%
«
O
S
VA
TABLJB XIVe
•
«
H
S
mg/ml
8
Background
L ight
S
sO
S
g
h$
Average
Maximum
B efT ec ti on
g
VA
S
C ontinued
O
9
mg/ml
Background
Light
Average
Maximum
D e fle c tio n
D iffe r e n c e
D iffe r e n c e
mg/ml
mg/ml
Background
L ight
Average
Maximum
pef IA c t i o n .
Background
Light
D iffe r e n c e
D iffe r e n c e
mg/ml
mg/ml
Average
Maximum
D e fle c tio n
Background
L ight
Background
L ight
Average
Maximum
T le fl e c t.1 nn
Average
Maximum
D e fle c tio n
D iffe r e n c e
D iffe r e n c e
O
Galvanometer
Zero
M
O
Average
Maximum
D e f le e tl on
Amperage
A pplied to
E leetro d ea
V oltage
A cross
E le c tr o d e s
Ohms in
S e r ie s w ith
E le c tr o d e s
-4
O
H
v4
mg/ml
O
M
Background
L ight
VM
Average
Maximum
D e f le c t io n
'
O
03
O
O
S
4
4
S
s
xO
O
H
O
p-
H
mg/ml
o
Background
L ight
s
E
s
I
8
%
f
3
S
Vft
S
S
D iffe r e n c e
mg/ml
Background
L ight
Average
Maximum
D e f le c tio n
D iffe r e n c e
Average
Maximum
D e fle c tio n
D iffe r e n c e
CO
cn
M
O
O
Vn
— -----—
S
M
M
W
~
%
2
S
S
__________________________ pi—
M1
b*
^
^
M
8
mg/ml
Background
Light
Average
Maximum
D e fle c t!o n
D iffe r e n c e
«*
?»
I
o
n
BeedingS o f Cu, Mg, Zn, Ce; L i I n te m e l S tend srd
Average
Maximum
D e f le e t l on
Amperage
A pplied to
El eet.rodee
V oltage
A cross
E le c tr o d e s
Ohms in
S e r ie s w ith
E le c tr o d e s
VA
TABLE XV/
•
«r ~ ....................... - '
‘uontimxeii on n e x t pege
Galvanometer
Zero
•
Q
M
VA
Background
L ight
S
O
Average
Maximum
D e f le c t io n
H
mg/ml
O
H
&
mg/ml
O
H3
H
O
N>
O
O
M
VA
O
W
Background
Light
Average
Maximum
D e fle c tio n
p
D iffe r e n c e
mg/ml
H
11
10
10
mg/ml
17
D iffe r e n c e
•
•
H
VA
§
E
S
s
__________________________ y
D iffe r e n c e
Background
L ight
Average
Maximum
p e f I e c t io n
O
1AX S'lC/X
e
O
H
d
1S
s
§
S
5
\5
S
Background
Light
Average
Maximum
D e fle c tio n
D iffe r e n c e
mg/ml
Background
Light
Background
Light
Average
Maximum
T leflen tln n
Average
Maximum
D efI e e t io n
D iffe r e n c e
D ifferen ce
O
#
penuncoj
mg/ml
3m. o f D e fle jc tio n
F igu re 5
«* 2b —
Cu. Li
Cm. o f L e fle c t io n
F igu re 6
Cm. of D eflii c tio n
50
250
100
F ig u re 7
-ItO-
300
Cd. L i.
Cd. Li
Cd. Li
Cm. of Def
L i. Mg,. Ca. Zn
Cm, o f D e fl ic tio n
F ig u re 10
• 33 -
50
Too"
Cm, of D e f le c t io n
150
ZOO
F ig u re 11
- 34 .
Z50
Zn. Cu
Cm. o f D e f le c t io n
F ig u re 12
5
F ig u re 13
- 36 -
F ig u r e 14
- 3?
V II.
DISCUSSION
She d » t? o f TVble# IX throui^i XV w ere o M sin e d f i r s t .
In g e n e ra l
A n ely tl e a l p ro c e d u re s l l t h l u a Ie n o t en co u n tered end f o r t h i s reeeo n I t was
chosen f o r th e I n te r n a l s ta n d a rd .
In ch o o sin g th e I n te r n a l sta n d a rd method
ee e h e e ls o f comparison* I t wee hoped t h a t by a d ju s tin g th e e le c tro d e
system to produce a c o n s ta n t I n te n s ity o f l i g h t t h a t th e en erg y c a r r ie d by
o th e r e lem en ts would be com pensated f o r end a s in g le cu rv e o b ta in e d ; I .
th e a d d itio n o f <g, Zn and Cu, c u rv e s X I I I , XIV end XV, F ig u re 11, to th e
Ll-Ce s o lu tio n , curve X, would p o s s ib ly h e r e produced i d e n t i c a l cu rv es
w ith in e x p e rim e n ta l e r r o r .
The c u rv e s o b ta in e d from th e p l o t t i n g o f th e
calcium d a te . F ig u re 11, w i l l I l l u s t r a t e whet was found to ta k e p la c e .
There I s , u n d o u b te d ly , some e x p e rim e n ta l e r r o r p r e s e n t b u t I t could In no
way a cc o u n t f o r th e r e s u l t s ,
f t th e ,0 5 mg/ml c o n c e n tra tio n o f C s, curve
X, a d e f l e c t i o n o f 62 cm was o b ta in e d .
r e s u lte d In o n ly a d e f l e c t i o n o f $0 cm.
The a d d itio n o f *05 mg/ml o f Mg
In o th e r w ords, th e a d d itio n o f
Mg d e c re a se d th e I n t e n s i t y o f l i g h t p ro duced by th e calciu m o r In c re ase d
th e l i g h t produced by th e lith iu m .
From F ig u re 14, i t can be seen th a t
th e amperage needed to produce th e 62 cm d e f le c ti o n o f calcium was ,32
amps.
The amperage r e q u ire d to p ro d u ce th e 50 ea d e f le c ti o n in th e p re se n c e
o f Mg was .3 7 amp#.
To have to In c re a s e th e c u r r e n t l a o rd e r to g e t th e e ss e amount o f
l i g h t from th e I n te r n a l s ta n d a rd , as more Io n s a re added, to th e s o lu tio n
could be e x p e c te d .
tio n .
f t th e
In cu rv e XIV, Zn had been added to th e Ll-Ce-Mg s o lu ­
c o n c e n tra tio n o f .0 5 a g /m l o f C s, a d e f l e c t i o n o f 65 cm was
o b ta in e d , an In c re a s e o f 1$ cm in d e f l e c t i o n when Zn was added.
— 38 —
At th e
.1 mg/ml c o n c e n tra tio n o f Ce, th e d if f e r e n c e betw een c u rv e e X III end XIV
ie en ln c re e e e in d e f l e c t i o n o f 70 cm.
from f ig u r e 14, cu rv e XlV shows
Ie s e amperage used - ,01 s« p , le e s - th e n cu rv e X lII e t th e ,0 5 a g / a l o f
Ce.
th e ,0 1 a g / a l o f Ce th e curve X ItI re q u ire d .0 2 e a p . more th e n th e
curve XIV.
Curve XV Ie en a d d itio n a l In c re a s e in d e f l e c t i o n o f 20 e a * t
th e .0 5 ag /m l o f Ce ^nd » leo an a d d itio n a l In c re a s e » t th e .1 a g / s l o f Ce
o f hg e a ,
The eaper*ge u sed to produce th e d e f le c tio n # o f cu rv e XV was
.01 e#p. l e s s a t th e .0 5 a g /ia l o f Ca *ad ,0 9 a sp , le e s « t th e .1 mg/ml o f
Ca,
An ex am in atio n o f th e Mg c u rv e s , f i g u r e 10, t h a t was added to th e Ca
o f F ig u re 11 shows a v e ry s im ila r b e h a v io r to th e Ca o f F ig u re 11.
As more
elem en ts a re added to th e s o lu tio n th e amount o f d e f le c ti o n i s in c re a s e d ,
I,
th e Mg lone r e s u l t in th e p ro d u c tio n o f more l i g h t .
Ih e c ro s s in g
o v er o f c u rv e s XIV and XV o f F igure 10 does not r e a d ily len d i t s e l f to an
e x p la n a tio n .
The same c r o s s in g o v er o c c u rs on F ig u re 12, c u rv es XIV and XV,
which i s th e graph o f Zn,
In g e n e ra l, th e same s h i f t i n g o c c u rs in F ig u re
12 .
The c u rv e s o f Cu, F ig u re 13, a re o f two w idely d i f f e r i n g c o n ce n tra ­
tio n s and c o n se q u e n tly do n o t len d th em selv es to a g r e a t d e a l o f i n t e r ,
pro ta tio n .
The f a c t th a t th ey r e p r e s e n t d a ta o f such w id e ly d i f f e r i n g
c o n c e n tra tio n s may p o in t to * need o f g e t t i n g more c o n c lu s iv e d a te .
Some
o f th e e r r a t i c c h a r a c te r o f th e o th e r c u rv e s may be due to t h e i r b e in g
p l o t t e d on such a la r g e s c a le .
fie d .
Any s l i g h t e r r o r would be g r e a tly magni­
I t i s d e s ir a b le to o b ta in d a te t h a t would c o v er a much w id er range
o f c o n c e n tra tio n s b e fo re any d e f i n i t e c o n c lu sio n s a re draw n.
- 39 —
In g e n e r a l, to eummprtse th e p re c e d in g fig u r e * 10, 11, 12, 13, th e
ln e re e e e In number o f elem ents p r e s e n t ln c re e e e e th e s e n s i t i v i t y (ea o f
d e f l e c t i o n ) o f e l l elem ents p r e s e n t.
The c u r r e n t needed to produce t h i s
ln e r e e s e In s e n s i t i v i t y d e c re e se e ee more elem en ts e re rd d e d .
I f th e
p re s e n c e o f th e edded elem ents bed e r r r l e d more o f th e c u r r a n t which had
o r i g i n a l l y been used by th e I n te r n e ! e ta a d s rd , I t would seem lo g lc e l t h e t
I t sh o u ld h e re been n e e e se e ry to ln c r e s s e th e c u r r e n t s u p p lie d to th e
e le c tr o d e In o r d e r to r e - e e t e b l i e h th e d e s ir e d I n te n s ity o f th e l n t s r a r l
s te n d e rd .
Since th e c u r r e n t used wee e c t u s l l y l e s s re more elem en ts were
added, some o th e r e * p l# n « tlo n I s n e c e s s a ry ,
fin e x p la n a tio n o f how one
elem en t c o u ld s e t upon a n o th e r to #euee th en b o th to produce more l l ^ i t
f o r m e m issio n s p e c tre co u ld n o t be found.
However, a stu d y o f the
n a tu r e o f th e l i g h t so u rce taey p o s s ib ly r e v e a l an e x p la n a tio n .
The d a te sum aprleed in th e c u rv e e produced from T ab les IX through Xf
In d ic a te d t h a t p e r t o f th e I r r e g u l a r i t i e s co u ld be due to th e p re sen c e o f
th e lith iu m .
>a r r e s u l t , eedatwti was chosen as th e n e x t I n te r n a l sta n d a rd
and lith iu m wee u se d a s sn a d d itio n a l elem ent alo n g w ith Mg, Ce, Zn and
Cu.
C urves I I , I I I , I f and V, f ig u r e 9 , e re th e p l o t s o f L I, a s th e ad d i­
t i o n a l elem ents w ere added.
I t Is e a s i l y seen t h a t as th e number o f
e lem en ts i n th e s o lu tio n in c re a s e d , th e I n t e n s i t y o f th e LI d e c re a se d .
The
f a c t t h a t th e Li v a lu e s seemed to approach a c o n s ta n t v a lu e o f d e f le c tio n
was p ro b a b ly due to th e e p e e tr e l resp o n se o f th e m u l t i p l i e r p h o to tu b e .
An
e x am in atio n o f f i g u r e I h w i l l show t h e t en Inorwasp in amperage wss re ­
q u ire d to produce th e d e s ir e d s p e c tr e ! i n t e n s i t y o f th e in t e r n a l stan d ard
a s th e number o f elem en ts In th e s o lu tio n in c re a s e d ,
— ho —
T his Is e c o n tra -
d i c t i o n o f th e r e s u l t # o h t# Ined from d a ta o f 7 « h lee IX th ro u g h XT.
e x a a ln F tlo n o f c u rv e e I I . I l l ,
An
IT end V o f f i g u r e s 5» 6 , 7 end 6 shows
*n ln e re e e e In s e n s i t i v i t y o f th e e le a e n te Mg, Ce, Zn end Cu »e each o f
th e s e a d d itio n * ! elem ent# wee added to th e s o lu tio n .
A review o f th e r e s u l t # o f th e s e two group# o f d a te w i l l show th a t
w ith LI ## th e I n te r n a l s ta n d a rd , th e a d d itio n o f d i f f e r e n t elem ent# to
th e s o lu tio n , c au se s an In c re a s e in s e n s i t i v i t y o f a l l th e elem en ts
p re s e n t.
The amperage needed to produce t h i s ln e ra e s e In s e n s i t i v i t y SJtm
c r e a s e B a s more elem ent# a re added.
W ith cadmium a# th e i n t e r n a l e ta n d a rd ,
th e s e n s i t i v i t y o f th e elem ent* p r e s e n t i s a g a in In c re a se d a# more elem ent#
a re added, h u t In t h i s c ase th e Rjnperage re q u ire d to produce th e normal
I n te r n a l stan d a rd had been In c re a s e d .
W hile th e Mg, Ce, Zn end Cu were
in c re a s in g In I n t e n s i t y , th e I n t e n s i t y o f th e LI was d e c r e a s in g as th e
number o f elem ents In th e s o lu tio n In c re a s e d .
In o r d e r to g a in f u r t h e r In fo rm a tio n on what th e e f f e c t o f LI might
h e , th e d a ta in T ab les I , T I, TH and T i l l were o b ta in e d .
In th e se ta b le s
th e e lem en ts p r e s e n t a re th e same »e In T ab les I I , I I I , IT and T except
t h a t LI Ie a b se n t In a l l e a s e s .
In th e d a ta shown, th e amperage# a re seen
to in c r e a s e a# th e number o f elem en ts in th e s o lu tio n was In c re a s e d , and
th e In c re a s e In th e I n te n s ity o f th e l i g h t p ro d u ced , ee more elem ents were
added, was n o t n e a r ly eo g r e e t a# i t we# when Li wee p r e s e n t .
— h i «*
■i
m i. aau a
1.
The l l j h t so u rc e w » a c r e th r n ed eq u ete f o r th e ep ec tro e e o p e a v a ila b le
f o r t h t e I n r e e tlS F tto n .
2.
The low er l i a i t s o f d e te c tio n wee lim ite d by th e background l i g h t p ro ­
duced by th e submerged e le c tr o d e ,
f u r t h e r e x p e r ia a n ts t io n could p robab­
l y reduce t h i s lim it in g f a c t o r .
3.
When lith iu m i s u sed e s th e i n t e r n a l s ta n d a rd , th e a d d itio n o f th e
elem en ts s tu d ie d , end in c r e a s in g t h e i r c o n c e n tra tio n , ln c re e s e e th e
s e n s i t i v i t y o f e l l elem ents p r e s e n t,
h,
I f eedmium i s u se d es th e i n te r n e ! e te n d s rd , th e s e n s i t i v i t y o f lith iu m
d e c re a se s w ith a d d itio n o f th e elem en ts s tu d ie d end w ith t h e i r in c re a s ­
in g c o n c e n tr a tio n .
I f lith iu m i s n o t p r e s e n t th e ln o re e e e in s e n s i t i v i t y
o f th e e lem en ts s tu d ie d i s n o t n e a r ly so g r e e t.
5,
W ith ti s in g le elem ent in e s o lu tio n , I t e c o n c e n tra tio n c o u ld be r e a d ily
d eterm in ed from e known c o n c e n tra tio n c u rv e ,
6,
from th e b e h a v io r o f th e elem en ts s tu d ie d , i t i s th o u g h t t h a t due to th e
s h i f t i n g o f th e c u rv e s caused by th e a d d itio n a l e le m e n ts, a group o f
unknowns from c lo s e ly r e l a t e d s o u rc e s , h a v in g th e seme elem en ts p r e s e n t,
co u ld be a n a ly s e d q u a n t i t a t i v e l y by t h i s method,
"each group o f unknowns
would p ro b a b ly need a d i f f e r e n t s e t o f known c u rv e s,
7,
I t i s a p p a re n t from th e c u rv e s p re s e n te d in t h i s work t h a t each elem en t
h a s a c h a r a c t e r i s t i c c u rv e .
M-
J"czmvLaa%mfT
Ih e r u th o r w ish es to ^eknow lease th e v p lu e h le s s e is te n e e given
th ro u g h o u t t h i s In v e s ti& e tlo a hy C r. B, W h o crlff.
He e l bo w ish es to tn e ak
th e E eseerch C o rp o ra tio n o f Sew Io rk f o r a sk in g t h i s in v e s t I g e t ion p o s s ib le
th ro u g h t» g r a n t.
M ONTA NA S T A T E U N IV E R SIT Y L IB R A R IE S
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