General Report on Tunny

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12C Page 21

Fig. 12 (II) Some Typical letter counts.

	P	ΔP	Ψ'	ΔΨ'	ΔD	Χ	Z
/	4(a)	91	118	1159	128	98	110	/
9	544	78	107	4	127	99	81	9
H	67	82	97	17	128	99	94	H
T	123	56	108	4	98	101	124	T
O	89	121	107	18	128	101	108	O
M	180	69	100	47	105	106	89	M
N	212	66	98	7	78	95	95	N
3	1(a)	157	99	2	118	101	114	3
R	159	77	87	11	87	105	110	R
C	44	73	84	53	84	98	105	C
V	21	64	100	153	80	99	89	V
G	94	127	109	32	125	114	93	G
L	87	76	85	17	98	118	104	L
P	51	90	116	47	99	110	123	P
I	137	50	121	10	94	89	87	I
4	3(a)	52	79	5	71	105	93	4
A	161	136	96	13	96	90	82	A
U	81	224	109	52	148	103	99	U
Q	23(b)	79	103	186	92	97	88	Q
W	38	67	108	52	70	114	104	W
5	200	326	106	160	170	108	106	5
8	197	144	75	572	101	107	112	8
K	60	45	106	154	66	99	95	K
J	6	194	96	46	115	96	77	J
D	71	83	91	14	71	91	85	D
P	42	156	103	56	107	83	104	F
X	1	83	79	168	87	93	106	X
B	57	32	111	47	55	104	101	B
Z	26	65	81	13	81	103	108	Z
Y	7	84	94	62	88	95	106	Y
S	110	90	121	14	109	75	110	S
E	305	63	106	5	96	104	98	E
Total	3200	3200	3200	3200	3200	3200	3200

Notes.

All counts are taken from the same message ciphered on the keys of Grilse Jan. 10th 1945. (26 dots in μ₃₇).

The bulges in the counts of P, ΔP, Ψ', ΔD have been explained. Ψ', Χ, Z show (for all practical purposes) typical random count in which every letter occurs an approximately equal number of times. The counts of D, K, ΔΧ, ΔZ must also be flat.

(a) /34 should not occur in P. Their occurrence is due to corruption.

(b) Q rarely occurs in 'letter-shift', but is quite frequent in figure-shift, where it corresponds to 1 (one).

(c) Note how the frequency of letters other than / depends on the number of crosses in them. For 26 dots in μ₃₇ a = .65 b = .77.

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