Magic Age Card. Manuscript on paper.

1 leaf, 200 x 323mm; watermark of crowned lion with scepter and fascia of arrows, very like Churchill #88, which he identifies as English colonial, dated 1762. Seven columns of numbers, with brief explanation on verso. Folds, some beginning to split. Manuscript 18th-century game or puzzle which allows whoever knows the key to accurately guess anyone's age (or chosen number in a "pick-a-number" scenario). We won't divulge the secret--but it has to do with binomial number systems--and it works! Similar magic age tables persist to the present day in a somewhat different form.