.. 

.. 

•• 0. 

• REF ID:A60499 

WAR DEPARTMENT 

OFFICE OF THE CHIEF SIGNAL OFFICER 

WASHINGTON 

Omnander Klnpea. 

. 1. !he •'1ldl' to Which JOU referred th1• mol'JllDg waa mad• at •• SDfOl'llal reque•' of 7our pNdeo•••or, oo.amer Gocl1da, and Lieu,. LoTent'bal, Sa 

aomseatlon with a rat'ber uonpl1aa'8d clphor ma.oh1Jle, whiah was being oom1dere4 

tor Ull9 1D \ha Xaw.1 ••nloe. 

a. !hl• lnwatlgatlon extended Oftr a pa.rlo4 of about alx month•• 

but I did •ot, ot course. deYo~o all llW' aTa11abla tillll to lt - onl~ auoh aa 

001114 be apare4 tl-oa Ill' more S..41a te dut le• 1n the ottloe. 

1. !he amq paaaed '1u'ough aenral atagea. .Plrat, a oaretul aur- .,., •• made of the '1P9 ot orn,osraa produoad bJ the apparam.· !rhb lzm>1Te4 NH&rah into the meohanico-eleo,rloal :teatura1 ot the maohlmt muaJ of whlah 

wre DDY•l, and reaul tad lll produc1zg orn>tasrsa1 of aona14erable oaaplexl V• 

JJe'-11•4 1D.,_e·Ugatlon, howw:r, oonTlnoed me Uutt claw tor 1ndeo1pheraldll'1'• 

e"Mn ot a relati'N nature• put :tortlh b;v 'hose intorestea. •re :not WDft'&nte4• lt 

all tb8 tao'or• oonmowd with the UH ot tho maahlm la the aUltal'J or •Tal 

senlae wre talrBn illto oons1da1•atlon. 

'I' 

"• !he next step was• of aourae, 'o 11t,omp-t to establillb. a boc1'1' of 

prlnolplea and a method ot procedure tor d;rntanal.7tlo :reduo,loa ot the dl•patoh-

•• ,,hioh would be produoad under sen1oe oond1t1o:u. In thi• I was auoa•••tal, 

and 1atlatled IQ'•lf that auah reduotioa •• ..,, on17 poa1lble bat "1'1' pi-aotl- oa\le. 

Ba f,here romalnecJ. ho•wr. the quas·non ot demonatrat1228 the '"1th 

· of the Tal'I0111 hJ'pothe1ea ••1iablllhe4. A. 1et ot tan teat •••as•• •• preparet. 'b7 the Code and Slgaal seot1on1 laaH4 upon ne unmp,lcm that the e1111q woul4 

Jmow all '11&' tbe:re 1• 'o be JmoWD •• :resarda the •oh1De and lt• tmlo'i!:!.\ lnl.' 

would not know the wll'lll8 ot "118 alpbelt 'llhael1. !he lJ:idS.aawr woftt tor • ._ aage, 1n order to enable the :reo:lpS-t to ••t hia maohlne prope:rlJ tor cteolpher1Ds1 waa 8hown :la ol•ar on eaoh •••aae, as '111• would 'be ~ oan 1n aotuai 

pztao1i1oe mal••• '119 •P tea wre f'uther aamplSaated b1 the u• of a oode booJc• 

or •cne other auba1dlar7 oipher a1•t811 for 41'8U1•lns the· 1ndlaato1'8. • 

&. !he first ot ••• 41apatohe• 1111.a aolw4 at"8r approx:blate- om •*'• lnteml• etuq of the data based on all ten •••888•• !hi• lensth ot 

ts-, howwr, slwa m rel:labl• lndex of the length o:t 1ilme that would 'be :req'lilre4 1n ao,ual pJ.'aO\loe, beaauae IJl&1V' other tao,ora, •uab u per•onnel, Tol- ,_ ot data, special 1ntona.,1on t.roa gemral intolllsenoe, and ao cm, woul4 all 

ban a Wl'J det1n1'8 and 111por'8nt 1nt111112loe on this qU111iSma, ae 7011 are wll 

&WAN. I wa11 all alom, ae regard• the anal.7&18 ot the data, and had .,, '1le 

1llfJ)l,•1t idea a1 to •at aD1 ma1aage wu about. It la rq oplzilon that wltll a 

la1'8• • •11-tra1m4 •'o.tt, and aourcea of outa14• lntelllgeno• '11&\ aft unal.17 

&T&llable, '11• proae•• oould be aooompllllhe~ wlthm a 11paoe of 'IM ahor1i •~uah 

@'pp roved for Release by NSA on 09-06-2013 pursuantto 

0

E .0. 1352a 

-
REF ID:A60499 

to make the o.nal7sla of mensages of me.Jar 1Pl:portanoe ver1 Yaluable to an ••IV• 

'· Regardles1, howenr, of how long it took to solve that t1raii •9-

sage, the nolu,1on ot the rest ot them was made very muah a1mp1e:r as a reaul t ot 

a rnost 1n1;ereeUns sei-1ee ot arial7tic •"epe dewloped oo1nc1dent with the solution of the ti:ret message. In :raot. it was shown tii..a.t the solution ot but two 

or tl:aree· linoa o-£ text of one massage was all that ms neoe11aar;,. 911t1 would be 

ditt1oul1;, perhaps, depending on how much text "3.s available, but onoe done, '11• 

rest follows ratilar eae11,-. I do not moan to sq that only wo or three llnaa 

o·l cipher text are necesl!llll'J', but thl.\t t.be .tm.'\l~·si:t ot tho de.~ based on a oona!derabla volume ot te:x.t, when applied on17 to two or three 11•• ot o• •••as•, 

wlll re•ul t in the solu·Uon ot tho•e l!nes, tmd from th..-"\t, tlte :reat :tDllows in 

rapid o:rdar. 

a. It la neaea9ary to say tbnt the w11'1ng o:t the plaw in the 1'881' 

ot tho 1'1A.Ob1ne was Imown io me :tn thls test, 1 t haT1JJG honn nsawmd tbnt th1S 

part of the elttotr1oa1 arraJJgements would be the 8arna for all maohble•• It see ... ed neoeasnr~, o~ course. to eats.bl 1eh procedure for nnnl.1's1o men the latter ill 

un:t:nown. While no actual massages were presented for solution, on account o~ the 

laok ot time and peraOD11611 Mvertheless a set o't about 100 messages had. bea 1'1'•-

parod soma time prev1ousl7, and the cipher diepo.tohes were oaretull7 u:amiDed Sn 

oonnactlon with their plain text, and diasrama of tlw wiring of the oipber Wboel•. 

!Jie da~a al1owed that given a autflc!ent number ot massage• (tile trn:t:tic of JI.AA 

for one dq during active operntinns m;nzld be more than aufttc!ant) nolution 

oould be achieved within a praot!oable le:nath ot t1me. I would ewn go ao far 

J10'\'1 as to wnturo the op1n.1on that it ml(Jht be done ,.,ith thiZ"tf oi- no aeacas••• 

9. ot oourso, w1 th an tmderstnnd:lnr. of the raeebanica of the tma1¥Gl•, 

suggestions for the 1mproyeme11t of the apparatus, with a Tiew to 1ncrea111JJ8 the 

degree of oeoroc:1, presented thfluelws. !hese 9 ElJ1Cl the r.iethod of solution. "8N 

001"'1'UD.loa,ed to members of 7our aect1on. 

10. I wish to take this oppor"1mlt,' tio say that llr. Bogle ot 70ur 

seot\on rendered very- Taluable a1sistance in the way o~ oomp11l:D6 special table•, 

under 1111' dlreot1on. :t also wish to add that I wa.8 "ftt!'J' gla4 •o haTe had the op.· 

portunl 't7 to conduct this :lnvest1gat1on1 tor I had the good :tortun.o to deTelop. 

eeTeral new principles in a~:lll, the value of which will no doubt manlt.st l'-

••lt 1n rq min work at sOMe. future time. 

w. P. :rr1e.ms.n, 

0?7Ptana1Jat, Signal Corps.