51. Arithmorems.--This class of riddle is of recent introduction. The Arithmorem is made by substituting figures in part of the word indicated, for Roman numerals. The nature of the riddle--from the Greek arithmos, number, and the Latin remanere, back again--will be easily seen from the following example, which is a double Arithmorem:-

H, 51 and a tub--a fine large fish.

A, 100 and gore--a sprightly movement in music.

R, 5 and be--a part of speech.

U, 551 and as and--a Spanish province.

To, 201 and ran,--a stupefying drug.

R, 102 and nt--an acid.

OU, 250 and pap--a Mexican town.

The answer is Havanna--Tobacco: Halibut, Allegro, Verb, Andalusia, Narcotic, Nitric, Acapulco.