MONTHLY LETTER REPORT NO. 9 ON THE POWER SOURCES STUDY

• Document Type: CREST
• Collection: General CIA Records
• Document Number (FOIA) /ESDN (CREST): CIA-RDP78-03424A002400070007-3
• Release Decision: RIPPUB
• Original Classification: K
• Document Page Count: 33
• Document Creation Date: December 22, 2016
• Document Release Date: September 20, 2011
• Sequence Number: 7
• Publication Date: May 31, 1957
• Content Type: REPORT

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MONTHLY LETTER REPORT NO.119I
on the
POWER SOURCES STUDY
Period: May 1 to Ma y 31,19S7_
STAT
STAT
STAT
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I Personnel
Total man-hours for period: 542
II Trips and Conferences
On May 23,
to discuss problems pertaining to measurement of thermal con-
ductivity of zinc antimonide over the temperature range of interest in the
development of a thermoelectric generator. Many details of the design of equip-
ment for such measurements were discussed, and improvements in the proposed de-
vice were evolved.
On May 22 and 23, attended the Eleventh Annual
Battery Research and Development Conference (sponsored by the U. S. Army Signal
Engineering Laboratories) at Asbury Park, N. Jo, which featured, in addition to
papers in the field of batteries, presentations on solar energy and nuclear and
thermoelectric devices.
III Progress Achieved During the Period Covered
A. Laboratory Work
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to Several systems of improving the high-temperature stability of
bonds between zinc antimonide and.. contact pieces have been investigated. The
conditions to be satisfied are rather stringent: the bond must be solid at the
highest temperature experienced by the hot junction; it must possess a low elec-
trical resistance at all temperatures; its mechanical integrity should not diminish
after prolonged heating in air; and its ingredients should not have deleterious
effects upon the performance of the complete thermocouple, if they diffuse into
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.the zinc antimonide. It was.found that electroplated layers of nickel or iron
stripped from the zinc antimonide surface after heating. Electroplating of an-
extremely thir layer (1-3 microns-.t hick) of silver on the zinc antimonide,
followed by admixture of an alloy of lead and tin resulted in good bonds, but
adherence of the silver to the zinc antimonide could not be reliably controlled.
Two promising methods have been found which produce excellent bonds at room
temperature, and whose products are being tested at elevated temperatures.
One relies on the alloy formed by zinc antimonide and pure tin for the bond;
the other employs a small amount of silver, previously electroplated on the con-
tact piece, to raise the melting point of the tin-zinc antimonide alloy.
Improvements in the handling properties of zinc antimonide pieces have
resulted from preparation of the alloy in a two-step vacuum fusion. The weighed
ingredients are placed in a Vycor tube, and melted while being pumped in a
vacuum system. After being sealed off, the Vycor tube is placed in another fur-
nace, and the molten alloy agitated to assure complete mixing. Material prepared
in this manner has exhibited greater uniformity and less occluded gas than that
prepared without the initial melting and evacuation.
2. The activation period of bromine-activated silver-silver bromide
cells has, been reduced from several hours to less than one minute. This improve-
ment has come about through careful adjustment of the components as they are being
assembled, and by monitoring the electrical resistance. while doing this. A number
of cells prepared during the reporting period have developed the full expected
voltage in less than one minute after the bromine was admitted to the cell.
Reduction of the internal resistance of activated cells to less than
the designed value of 900 ohms per square centimeter has been achieved. Part of
this reduction in resistance has been the result of use of layers of silver bromide
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which are less than half the customary thickness.
It has been found that the life of cells made up to this time has
been limited to the life of some solder joints in the associated test equip-
ment. Elimination of these joints is expected to'increase the cell life
greatly.
B. Study Program
This portion of the program has been neglected, in order to devote
more time to the laboratory work described above.
IV Plans for Next Month
Testing of complete thermocouples, prepared as outlined above, will
be carried out under conditions approximating actual operation of the thermo-
electric generator. Modifications in the composition of zinc antimonide will
be made, to compensate for the diffusion of bonding material into the alloy.
Continued refinements in the techniques of preparation of bromide-activated
cells will be explored.
June 26, 1957
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MONTHLY LETTER REPORT NO. 8
on
POWER SOURCES STUDY
Period: April 1 to April 30, 1957
Reference:
STAT
STAT
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I Personnel
STAT
Total man-hours for period: 487
II Trips and Conferences
There were no trips and conferences involved with this pro-
gram during the reporting period.
III Progress Achieved During the Period Covered
A. Laboratory work
1. The stability at elevated temperatures of two thermo-
couples - one made from constantan and zinc antimonide
originating in the TGK-3 thermoelectric generator and the other
from constantan and zinc antimonide prepared in the laboratory -
has been determined. With the source temperature approximating
350?C and the sink temperature about 20?C, the actual temperature
difference between the hot and cold junctions was about 280 to
3000. Both of the."t ermocouples described above were subjected
to these conditions for more than 300 hours. At the end of
this time, the thermal e.m.f. had changed by about 2% in both
cases. It is interesting to note that the couple prepared
from TGK-3 material increased in thermal e.m.f., while that
prepared from our own material decreased. This may be explained
on the basis of diffusion of silver and tin from the bonding
material into the zinc antimonide pieces. Small additions of
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these elements to the TGK-3 zinc antimonide result in an in-
crease in e.m.f. Since its content of these elements is already
at the optimum value, material produced in the laboratory de-
creases in e.m.f. upon addition of more tin and silver.
The technique for bonding was modified to include nickel
plating of the ends of the zinc antimonide prior to bonding.
This was done in order to diminish the deleterious diffusion
of tin and silver from the bonding material into the zinc anti-
monide under the influence of elevated temperatures. It was
found that oxidation of the nickel caused it to chip off during
the bonding process despite the fact that its coefficient of
thermal expansion approximates that of zinc antimonide. It was
also observed that some nickel was electrodeposited on the
sides of the zinc antimonide, providing an electrical short-circuit
and reducing the observed e.m.f. Despite these difficulties,
an efficiency in excess of one per cent was observed for a
thermocouple made from constantan and zinc antimonide produced
in the laboratory. The efficiency calculation was predicated
CTOT
2. Bromine-activated silver-silver bromide cells
embodying a new, protective, conducting paint have been pre-
pared. Several cells were made, exhibiting the full expected
potential of 0.98 volts, although this value was not reached
for several hours after activation. Increasing the load current
appears to decrease the time required to reach full voltage.
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Use of metallic coatings on the silver to prevent corrosion by
the bromine has been investigated with some promising results.
B. Study Program
A new group of translations from the Russian periodic
literature has been received from Infosearch, a British transla-
tion service. Among the papers included is a description of
the design and performance of the TGK-3 thermoelectric generator.
From comparison with our own data, it would appear that the
specimen we examined was somewhat better than average.
IV Plans for Next Month
Substitution of a thin coating of iron for the electro-
plated nickel at the ends of the zinc antimonide pieces will be
attempted. Difficulties are expected as a result of possible
thermal shock experienced in making bonds. Other refinements in
bonding techniques will have to be made to accommodate this
change. Nickel-plated components will be employed in experimental
gas-activated cells. In addition, several load - and life - tests
will be performed and the production of brominated silver foils
under controlled conditions will be carried out. The elimination
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of the delayed activation time will be attempted.
May 27, 1957
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MONTHLY LETTER REPORT NO. 7
on
POWER SOURCES STUDY
Period: March 1 to March 31, 1957 _ ._
Reference:
STAT
STAT
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I. Personnel
STAT
Total man-hours for period: 533
II. Trips and Conferences
On March 26 a summary of the past year's accomplishments
CTOT
and plans for next year were presentee at a meeting at.
Briefly, it was stated that the thermoelectric- STAT
generator portion of the study would continue toward the development
of a working device, but that additional effort would be applied
toward the development of improved therocouple materials. The
objective of this materials search would be the replacement of the
constantan negative branch of the thermocouples with a semiconductor
as well as the general improvement of the performance of the generator.
The battery portion would also continue in the development
of a gas-activated bromine battery. There would be added an investi-
gation of the feasibility of an electrochemical system employing
ground water as the electrolyte.
Rather than maintaining the study program as a separate
entity, it was suggested that this portion of the work be considered
an integral part of the thermoelectric-generator and battery investi-
gations whenever applicable.
III. Progress achieved during the Period Covered
A. Laboratory work
1. Using an alloy of silver, tin and lead, it has been
found possible to produce durable bonds between zinc antimonide and
steel contact pieces. The technique consists of electroplating
silver on the steel, coating the ends of the zinc antimonide with a
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commercial "tinning compound" and passing large electric currents
through the assembly while it is subjected to moderate pressure. By
adjusting the thickness of the silver and the "tin" layers, the
composition of the bonding material may be altered. Using material
obtained from the TGK-3, a zinc antimonide-constantan thermocouple
has been produced and is being subjected to a life test. The high
temperature in this life test is controlled at 350?C and the low
temperature is that of running tap water (less than 200). Provision
has been made for measurement of temperatures at several points.
Preliminary indications are that the stability of the TGK-L3 material
in this configuration is greater than that observed in the TGKG3
thermoelectric generator itself.
The coefficient of thermal expansion of a specimen of
doped zinc antimonide prepared in the laboratory has been measured.
Although the apparent coefficient of expansion approximates that of
nickel or some steels (15 x 10?6/?C), there is a definite change.in
the coefficient after the material has reached a temperature in
excess of 350?C. It is suspected that this phenomenon results from
imperfect annealing during the casting process. This hypothesis is
being investigated further.
2. A review of previous work on bromine-activated solid
electrolyte batteries has shown that a redesign of the experimental
single cells and facilities for their assembly is necessary. This
has been accomplished, and several cells of the new type fabricated.
Particular emphasis is being placed upon reduction of internal
resistance of the cells upon study of the effects of water vapor on
their performance.
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B. Study Program
No special emphasis was placed on this portion of the study
during the reporting period.
IV. Plans for Next Month
It is planned to continue the measurement of properties
of complete thermocouples using zinc antimonide prepared in the
laboratory. Refinements in the bonding technique to increase the
number of bonds which can withstand the high thermal gradient will
be sought. The work of the gas-activated battery program will
continue as during the present reporting period.
April 25, 1957
STAT
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MONTHLY LETTER REPORT O. 6
on the
POWER SOURCES STUDY
Period: January 1 to January 31, 1957
STAT
STAT
STAT
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I. Personnel
Total man-hours for period: 293
II. Trips and Conferences
On January 17,
met with other interested parties
in Washington to discuss the status and plans of the Study and to establish the
requirements to be met by power sources considered in the Study., It was dis-
closed that a TGK-10, an improved version of.the TGK-3 currently under investi-
gation, might become available to us for study.
On January 24,1 Imet with personnel of the Diamond
Ordnance Fuze Laboratory to discuss power sources of mutual interest. DOFL is
investigating improved zinc-silver oxide systems, which are relatively conven-
tional batteries. A small amount of work at that installation is devoted to a
study of the feasibility of using moist earth as the electrolyte and separator
of a reserve battery. It would be possible, should the system prove workable,
to store the electrode system indefinitely, then to insert the assembly in the
ground when it is desired to use the battery. Removal from the ground would
restore the battery to an inactive status. DOFL also made an offer of assis-
tance in the form of acting as intermediary in obtaining ASTIA reports, or in
approaching the Franklin Institute for information concerning their programs.
. On January 24,
Details of techniques which
has used for bonding of
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zinc antimonide to steel contact pieces were discussed in detail, as were modi-
fications in composition of the impurity mixture to be added to the material. STAT
III. Progress achieved during the Period Covered
A. Laboratory work
1. The TGK-3 was maintained at its operating temperature for a total
of 1296 hours, and the following changes noted since the start of the experiment.
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Property
Original Value
Final Value
Open-circuit e.m.f., volts:
"Anode" circuit
5.20
4.55
"1-3t' circuit
3.04
2.70
Efficiency, per cent
0.917
0.749
Upon termination of the experiment, the TGK-3 was disassembled, and
found to contain a total of 168 thermocouples, with 108 couples in the "anode"
circuit, and 60 in the "l-31! circuit. Samples have been furnished for spectro-
scopic analysis, and others will be subjected to conventional chemical analysis.
2. A quantity of zinc antimonide containing appropriate additions. of
tin, bismuth and silver was prepared. This was found to be capable of being
sawed into small pieces by use of a diamond wheel. Some of these pieces were
electro-plated with silver as an initial step in the development of bonding
techniques for assembly of thermocouples. It is planned to bond the zinc anti-
monide to steel contact pieces by plating the surfaces with silver (or plating
one with silver and the other with. tin), then to form an alloy at the bonding
point by passage of a large electric current. A jig for holding the pieces
during this operation has been tested, and initial results have emphasized the
necessity for formation of an adherent coating of silver on the steel.
B. Study Program
Most of the information derived from the study program is described
briefly under "Trips and Conferencest'.
IV. Plans for Next Month
Interpretation of the information derived from the chemical analysis
of the TGK-3 will take. place, correlating the chemical information with the
observed electrical behavior. Details of construction will be carefully
analyzed and appraised.
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The development of reliable and reproducible bonding techniques for
zinc antimonide and steel will continue.
STAT
February 21, 1957
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MONTLY LETTER REPORT NO. 5
on the
POWER SOURCES STUDY
Period: December 1 to December 31, 1956
Reference:
STAT
STAT
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I. Personnel
STAT
Total man-hours for period: 305
II. Trips . and. Conferences
Due to the pressure of laboratory work, there were no trips or conferences
during the reporting period.
III. Progress Achieved. during-the Period Covered
A. Laboratory Work
1. The'TGK-3 thermoelectric generator has been maintained at a
temperature approximating its operating temperature for nearly 700 hours.
Periodic measurements of its output and efficiency have been made, with the
following results:
Time since Start Open-Circuit'E.m.f , Efficiency,
of Experiment, volts. per cent
hours "Anode" "1-3"
Ckt. Ckt.
0 5.20 3.04 0.917
360 4.88 2.86 0.853
695 4.60 2.75 0.798
Because the efficiency and output voltages are falling, albeit at a decreasing
rate, it is planned to continue the measurements for at least one more interval
of 300 to 400 hours, then to determine whether the apparent deterioration
ceases or continues.
2. Sufficient zone"refined material for production of a batch of
zinc antimonide has been accumulated, and production of such a batch was
attempted. During this procedure, it became evident that re-design of the
furnace used in melting was essential, and that has been accomplished.
3. The remainder of the laboratory work has been devoted to de-
signing equipment, procuring parts for equipment, and refining the design of
the finished thermocouple. In addition to the furnace mentioned above, there
has been completed a design for a re-casting apparatus for zinc antimonide.
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This will permit-the production of zinc antimonide in bars of the correct
cross-sectional area for inclusion in the finished thermoelectric generator.
Problems of procurement of parts for the "efficiency meter" and of
Advance ribbon for the thermoelectric generator occupied a significant portion
of the period. Obtaining heaters of sufficient stability, uniformity of
temperature, and ability to perform throughout the desired temperature range
of the thermoelectric power meter was a difficulty which has finally been
surmounted. With the arrival of the material which has been ordered, con-
struction of the measuring devices can take place.
B. Study Program
Because of the great emphasis on laboratory work, the study program
has been dormant during this reporting period.
IV. Plans for Next Month
Upon termination of the high-temperature study of the TGK-3 thermo-
electric generator, it will be disassembled. Its construction and design
will be studied in detail. Subsequently, chemical and spectroscopic analysis
of its components will be performed.
Production of zinc antimonide from zone-refined materials will continue,
upon completion of the re-designed melting furnace. Special techniques and
equipment for handling the material (sawing, preparation for soldering,
soldering) will be developed, Assembly of testing and measuring equipment will
take place at a rate governed by the arrival of ordered components.
It is planned to consult with
problems involved in handling zinc antimonide.
during the coming month, STAT
in order to obtain more information concerning soldering and contact-resistance
January 16, 1957
STAT
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MONTHLY LETTER REPORT NO.. 4
on the
POWER SOURCES STUDY
Period: October 1 to October 31, 1956
STAT
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October Report Draft
I. Personnel
Total man-hours for period: 532
II. Trips and Conferences
Page 1.
lattended the Electrochemical Society
meeting in Cleveland, Ohio, on October 1 - 3, 1956. In addition to reports of
progress in the conventional electrochemical battery field, there were some papers
in the semiconductor area which were of interest. In particular, a paper by Dr.
E. Mooser, of the Physical Institute ETH, Zurich, Switzerland, contained several
points of value for predicting the properties of compound semiconducting materials.
In discussions with Dr. Mooser and with Dr. T.C. Harman, of Battelle Memorial
Institute, Columbus, Ohio, much information concerning the state of the thermo-
electric genrator art in the United States, in Western Europe, and in Russia was
obtained. Dr. Mooser discussed his impressions of a paper presented by the Russian
/
_.,demician, Dr. A.F. Ioffe, and supported our previous impression that the Russians
are successfully expending a large amount of effort in the thermogenerator field.
Representatives of the Customer visited the laboratory on October 11 and
October 25. In the course of these discussions, it was decided to reduce the power
output of the proposed thermoelectric generator, as a consequence of the heat-
transfer observations described below. We also received from these representatives
several reports concerning European progress in the fields of thermoelectric generators
and fuel cells.
STAT
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October Report Draft Page 2.
III. Progress Achieved during the Period Covered
A. Laboratory Work-
1. Measurements of the available heat from various heat sources have
continued. A charcoal fire was found to yield approximately 550 watts at a
temperature of 3S0?C. At the same temperature,'a wood fire produced over 650 watts,
a small gasoline burner 120 watts, a larger gasoline burner over 550 watts, and a
2,000 watt electrical hot plate produced only about 1,000 thermal watts in the copper
:alorimeter. In order that the design of the final thermoelectric generator remain
realistic, permission was requested from the Customer to lower design specifications
to a flow of only 600 watts, rather than the former figure of 1,000 watts. The
permission was granted.
2. A quantity of zinc anthmonide was produced, following the directions
received from and some difficulty was experienced in obtaining
the substance in a form which was not brittle. Impurities in the raw materials are
suspected of being at fault, and some successful attempts to.purify them by means of
zone-refining have been made.
3. Design and construction of equipment for measuring the properties of
thermocouple materials continues. A device for measurement of resistivity has been
constructed, and an "efficiency meter" is being designed.
L. Means have been devised and are being tested for producing an adherent
layer of carbon on a silver sheet. The carbon powddr should be sufficiently adherent
and porous to permit its acting as a gas cathode in a bromine-activated silver-silver
bromide cell. Multi-cell arrays of stacked cells have been produced and are being
tested and perfected.
B. Study Program
Activity in this area has been confined to study of translations of Russian
literature, and to study of some of the documents left here by the Customer's
representatives.
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October Report Draft Page 3.
IV. Plans for Next Month
The laboratory work outlined above will continue, with emphasis on design and
construction of equipment and experimental gas-activated cells. We have been
apprised, by the Customer, of the impending arrival of a Russian radio powered by
a thermoelectric generator. Extensive measurements of the properties of this
system will be made on its arrival.
STAT
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MONTHLY LETTER REPORT NO. 3
on the.
POVIEt SOURCES STUDY
Period: September 1, 1956 to September 30, 1956
Reference:
.STAT
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September Report Draft
Page 1.
STAT
I. Personnel
joined the group for an indefinite STAT
period on September 24. They are concerned with the gas-activated battery portion
f the study.
joined the group on September 1, and is working as a STAT
technician on thermoelectric aspects of the program.
Total Man-hours for period: 334
there were no, trips or` meetings during. the re.por;ting period.
III. Progress Achieved : during the.Period Covered
A.' Laboratory Work
1. Heat-transfer studies for the proposed thermoelectric generator were
continued. Measurements of the available heat from various energy sources were
-extended to standard stove-type gas burners, and about 750 watts were found to be
available from this type of source. By use of a model, the transfer of heat from the
"cold" side of the generator to boiling water was found to be readily attained and
nearly equal to the heat available from the source employed.
2.. With the arrival of information fro concerning
production and testing of zinc antimonide-constantan thermocouples, a major effort on
design and fabrication of equipment for production and testing of thermocouple elements
has begun. A furnace for melting and annealing zinc antimonide has been constructed,
and design of a fixture for measurement of resistivity of the material is under way.
3. Initial design and planning studies for a bromine-activated silver-silver
bromide cell have begun. It is hoped that fabrication of some preliminary designs
can take place'in the near future.
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September Report Draft
Page 2.
B. Study Program
A series of translations from the Russian periodical literature has
arrived and has been studied. From these translations, it has become evident that
Russian efforts in the field of thermoelectricity are quite extensive. The material
contains much general theoretical and experimental information, but'lacks details,.
of specific materials and designs. A major benefit derived from study of these
translations has been the acquisition of criteria for intercomparison of materials
for thermoelectric generators.
IV. Plans for Next Month
Heat-transfer studies, using wood, charcoal, and other types of fires, will be
continued. Production of zinc antimonide will commence, in order that skill in
handling may be acquired. It is hoped that some experimental gas-activated cells will
be constructed and tested. Several members of the staff plan to attend the Meeting
of the Electrochemical Society early in the month, where they hope to learn of some
of the recent developments in the battery field and to become acquainted with others
active in the area,
STAT
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MONTHLY LETTER REPORT NO. 2
on the
POWER SOURCES. STUDY
Period: June 12, 1956 to July 31, 1956
~O. 2
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I. Personnel
Total man-hours for period: 339
II. Trips and Conferences
The staff visited with
to discuss techniques of handling thermocouple materials for area 2.
was willing to discuss general aspects of her development of high-
efficiency zinc antimonide-constantan thermogenerators, but would prefer to be
igaged as a consultant before giving detailed information concerning the prepara-
tion and handling of these couples. A search of the periodical and patent literature
shows that details of this sort can be conveniently obtained in no other way than
by direct consultation with one who has had experience with these materials. An
agreement of this type has been drawn up for the approval of the Customer.
III. Progress Achieved during the Period Covered
a. Laboratory Work: Experimentation on the proposed thermoelectric
generator can be subdivided into three areas:
.ea 1: Heat-transfer studies on models without electrical output. We are particu-
larly interested in the study of heat transfer from different kinds of fires, burners
or hot-plates to the hot-junction terminal plate. We want to be sure that such
heat transfer is adequate for the proposed geometry and temperatures.
Area 2: Study and adaptation of the zinc antimonide-constantan couple to
our needs.
Area 3: Integration of areas 1 and 2.
Preliminary skillet-type models for Area 1 have been constructed. However,
tests proved the internal thermal resistance of these models to be substantially
too high. Improved models are being made.
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b. Study Program: Several attempts to obtain copies of reports based
on Government-sponsored research in the battery field from ASTIA Document Service
Center in Dayton were unsuccessful. The agency reports that it is making every
effort to obtain these documents, and that it will forward copies when they are
available.
IV. Plans for Next Month
Continuation of experiments on the heat transfer aspects of our proposed
thermoelectric generator design is planned. Subject to the Customer's approval
a retainer agreement with
will be signed. Immediately thereafter
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--onsultation wit will be initiated. Our visit to the Signal Corps
Engineering Laboratory has been set for August 16 and 17. While the primary purpose
of this visit is to collect information for our study, we also have the Customer's
permission to discuss our gas-activated silver bromide battery system proposal.
Experimental work on this system may be initiated. A German, hermetically sealed,
rechargeable pocket flashlight cell has been received on loan from
for evaluation. Upon receipt of the Customer's
scientific papers and the ASTIA reports, we shall continue our study of the
terature.
August 7, 1956
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Monthly Progress Letter No. 1
Covering period May 11, 1956 to June 11, 1956
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I. Personnel
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Total man-hours for period: 160.
reported for assignment to the Study on May 14. While STAT
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and clearance by the Customer, he has been active in the non-classified STAT
aspects of the program.
II. Work Performed
a. 'Laboratory Work: Preparations have been made for some initial experiments
in the field of thermoelectric generators. Some general consideration has been
given to experiments involving gas-activated solid-electrolyte batteries. The staff
also visited
on June 5, in order to discuss supplies of component parts for gas-activated solid-
electrolyte battery systems.
b. Study Program: Memoranda on the following subjects were issued for
transmittal'to the Customer:
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1. Possible utility'to the Study program of Army liaison group in West Germany.
2. Electrical energy available from a fuel cell operating from a portable
hydrogen supply.
Russian development of a thermopile generator.
!t. German development of a thermocouple' generator.
In addition, the staff attended the Signal Corps Engineering Laboratory Battery
Conference in Asbury Park, N.J., on may 23 and'24, where they made the acquaintance
of personnel from the American Machine and Foundry Corp. and Ni . Cad Corp., both of which
are active in the production of wet batteries.
on May 31, visited the Customer in Washington. The
following topics were discussed:
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1. The reactivation of
2. Difficulties in obtaining U.S. information'for our study phase, due to
security classification of our contract number.
3. Difficulties in obtaining information from abroad.
4. Recent German and Russian developments in the following fields:
thermoelectric generators
nuclear batteries
hydrogen fuel cells
Our Customer indicated his willingness to help, wherever possible.
III. Plans for Next Month
In addition to continuing development of an experimental program, several
visits to authorities in the battery field and organizations sponsoring research
in the field are contemplated.
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has agreed to discuss her accomplishments in the field of thermo- STAT
electric devices. Another visit is planned for the Signal Corps Engineering Laboratory,
provided permission to discuss the silver bromide gas-activated system can be obtained
from the Customer.
June 18, 1956
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