## Nostrum by Mr E

### Puzzle explanation

Extra letters in wordplay spelt out “Why is a … like a …?” and “There’s a B in both”. The former is the question asked of Alice by the Hatter (the circled letters in the grid formed MAD HATTER – a description that doesn’t appear in the Alice books) in Alice’s Adventures in Wonderland, with the words RAVEN and WRITING-DESK omitted. Lewis Carroll intended the riddle to have no answer but many people have suggested possible answers nonetheless, including Aldous Huxley in the September 1928 issue of Vanity Fair, writing “because there’s a b in both and because there’s an n in neither”. The clues for 15ac and 9dn had an extra B in the definition (because there’s a B in both). The answers for 36ac DIRECTION and 2dn PLEASE were jumbled together to form their entries, completing the new riddle, “Why is a SAILOR like a CENTIPEDE?”. The intended answer, “Both have C legs”, using C = 100 and a pun on “sea”, was represented in the grid by MEDITERRANEAN in a C shape, and LEGS at the end of the middle row. The title refers to Mare Nostrum, the Roman name for the Mediterranean Sea.

### Clue explanations

Conventions: * = anagram, < = reversal

No Extra letter Answer Explanation [extra letter]
Across
1   PSYOPS POPS around S[W]Y
6   SUFFIX SIX around [H]UFF
10   DRIVING TEST VINGT in DRIEST
11   PINTABLES P + IN + TALES around B(ritain)
12   RASP RA[Y]S + P
14   ELMO L[I]MO after E
15 (B)right SIDE-ON (ED IS) < + ON
18   OSMOTIC OSMIC around [S]OT
19   BRIERED BRIE + RE[A]D
20   ARNE [L]EARN *
23   PREGNABLE BANGER < in P[I]LE
25   CHER homophone of SHARE
27   ANELACE AN + EL[K] + ACE
29   KIRMANS (MARKS IN ) *
34   OONT ON[E] in OT
35   DEVI DEVI(l)
36   DIRECTION DIRE + ACTION − A
37   TSESAREVNAS (SERVES SATAN) *
38   TENNIS (S + IN + NE[A]T) <
39   OGLERS (OR LEGS) *
Down
1   PAPERBACKED PACKED around (PER + BA[T])
3   ORTON [H]ORTON; ref. Horton Hears a Who!
4   PIASTRE PAST around I + RE
5   DILDO LI[E]D < + DO
6   SNEESHANS SNEE[R] + SHAN’S
7   UGSOME (p)UGS + (c)OME
8   FEAST AS in FE[E]T
9 com(B)ing ISSUING TISSUING − T
13   PACE-SETTERS SETTE in [S]PACERS
16   RIPE I in R[A]PE
17   BEGINNERS EB[B] < + GINNERS
21   REAR RE + A[I]R
22   CHINESE CHINES + [N]E
24   BENDING “prover” with B ENDING = “proverb”
26   SANCAI (A CA[B]IN’S) *
28   CONDOR ON in (C(hamber) + DO[O]R)
30   RIVEN (d)RIVEN
31   SENES SEEN * + S[T]
32   COPAL C[H]OP + (p)AL(m)