Book excerpt: Here is a look at Water in a Sieve and Blackkerchief Dick and twenty-two other books by Margery Allingham featuring Albert Campion. Campion, the fictional hero, was a man of action, who appears to be a "guileless-looking nonentity whom it is almost obligatory to underestimate." Any fan of Campion or Ms. Allingham's mysteries will enjoy comparing their judgments to Pike's.