REF ID:A39771 

• ' ROuTING and hOR~ SHEET 

~o be ~sc1 J~~cr ~revisions of Par. ~I 6 b, Oflice Rsgulaticns, OGS!30, 1534) 

-·-------·-------- Numbe·· 

Ef:.c:t ?ro!l' 

Action 

R&D 

f'o: 

TO: MR. C. A. ROWE, 

Patent Section, 

if.emorandum c 

0 

p 

Off ice of the Chief Signal Officer. 

Reference is made to memorandum of Mr. William F. 

Friedman, dated October 4, 1935, transmitting a draft of 

specifications and drawings and a request that a patent 

application be filed on his invention covering "Improvements 

in Cryptographs". 

The Patent Section is hereby directed to take the 

necessary action to invoke the "three year rule" under the 

provisions of Section 4894 R. S., in accordance with the 

procedure initiated by order of the Chief Signal Officer 

on August 21, 1935. 

(signed) Roger B. Col-on 

Roger B. Colton, 

Lieut. Col., Signal Cor~s. 

W.C.E. 

Initials 

and 

Date 

10. 

10-15-35 

Sheet '.'Io. 

@'pproved for Release by NSA on 01-02-2014 pursuantto E.O. 1352a 
REF ID:A39771 

• WAR DEPARTMENT • 

OFFICE OF THE CHIEF SIGNAL OFFICER 

WASHINGTON 

llr. lime. 

•::;. • I J. /.,. ;> I .f.,C Q .• c. ' I . I 

...... ---· ... 

8 

1. Oa page 4, llae 6, read •Figs. l - 7" instead ot 'ftga. 1 - 6•. 

2. On page 4, adcl at'ter llae 221 •n.g. 7 l• a llChaatic d1apaa 

of a modification ~the llcheae shown in Pig. 6.• 

3. On page 16, add the tollowiag1 

•A sixt.h •bodillent of this innntion la shown in. Fig. 7. In 

thia ton. of the ilmmtion use is ade of aingle ring COlm\ltatora which 

serft both as substitution co.matatora and control commatators in connection with a gang Ritch of 26 contact• operated "tv a uninraal bar • 

._Ting noir pe.rticalar reteraoe to 11.g. 7, the •l--ta 8hon 

therein are a1wt]ar in construction and f'ullction with the correapondl.ag 

•l••t• 8hOllD in the .:preceding .tigure. Ia thl• •bocl1mat ot the iaT&Dt.ioa, pq aitch 8' 1• 90 constructed that. when UV" tq 1• depnaaed, 

and ualwrl&l bar 44 1• actuated, •itch lnere 88, 1.88, 288, etc., 

diaengap contacts 90, 190, 290, etc., reapecU..-el.J", and engage coat.acts 

91, 191, 291, etc., reapecti~. The operation ot tb1a fora ot the 

ia'Rt8tlon la aa followa1 lhen a aeaage is to be enciphered, c011mtatora 

1, 2, .3, 4, and 5 are allped to a prearranged k91 and •itch 36 i• cloaed, 

settiag up a circuit •• tollOlf81 Bat'tc7 16 tbroqh Ritch 36, coaductor 

107, contaot 90, contact leYer 88, conductor 184 to contaet 29 ot elld 

plate 301, through com ltatora 1, 2, 3, and 4 to commtator S which direct• the carrent back through C0111111tatora 4, J, 2, and 1 to contact JOa 

ot end plate 301, throagh conductor 284 to contact lner 288, contact 290, 

cond1actor 106 to control •cnet 13 and thence back to ba.tte17 16. ~ 

control apet 13 11 enerpnd, ccmmtator 1 is rotated through l/26th or 

a rnolutioa; aettiq up a - Ht ot circuit• through the cipher trheela. 

The dnice 11 now r•d7 tor encipberillg the tirat letter or the ••aac•· 

It this letter ia th• letter A, the k97 corre8POJldi.Dg to it is depreaaed, 

and the COlltact lwer• ot aanc--it.cll 85 are caused to disengage the lClllt'~ 

set of 26 ooataata &Dd enpge the upper .. t. of 26 contacts setting up a 

circai t a• follow•• boa batterJ- 16 throuch oondact.or 23 to contact. 

46, coatact left.I' 18, contact 91, contact lner 88, oGDdnctor 84 to contact 

29, tbroagh and return through ~tator• 1 to 5 to contact 30, condactor 

184, contact lnw 188, contact 191, aomtuotor 9.3 to contaot l8'W' 19, 

contact 42, OOllductor 121 to indicatJ.ng dnice 14 which correapaad• to the 

letter Q, conductor 43, aitch J6 to battel7 16. After tbe letter Q la 

noted, kq A is rel•lled, all.osiDI the contact i ... era al gana ari:toh 15 

to 41 .... q• the upper set of 26 coatacta and enpge the lower •t ot 26 
. _ _., 

REF ID:A39771 

• • 

coataot1. At the instant when contact leYer• 88 and 188 both •ns:•c• 

eontaota 90 and 190 r1a9ect1Teq, a circuit is aet up .as tollowaa 

Batt.917 16 through nitch 36, conduotor 107, contnct·?O, cnntr.ct leYer 

88, conductor t84 to contact F.9 of end plate 301, throurh cDm11tator1 

1,. 2, 3 and 4 w comutator 5 which direct• the CUl'l"ent beck through , 

C011111Utator1 4, J,, .t and l to contact 30 ot end pl.eta .301, through conductor 

184 to contact leTer 188; contact 190, conductor 106 to control magnet 

13 and thence back to batta17 16. lben contl"Ol •fll•t 13 1• acain aergised, commutator l' 11 qain rotated through 1/26th ot a raYolution and 

again a 11ew aet or clrau.1t1 11 Ht up 1n tb.e aommtator units. 'lh• 

d.odce is now readf tor ancipber1ng the ucond letter or the m.eaaage.• 

4. On page 1)1 delete the first tan lines, snd le.st three lines 

beginniJJg Yith •xr tr.1 .t•. On page 14, delete the tlrat eight lines. 

s. Figure 5 is to be cba11£ed as l)er ... ple. 

lllUam F, 1r1tlduzi.