... Reviewed by Noel Thompson THERE have been stories in the newspapers recently, Your Canaries Can Still Sing and No Need to Kill Your Pets, dealing with the shortage of birdseed and enumerating substitutes for adequate feeding. When a few days later I picked up Bechhofer Roberts's book The Bird seed Pool (Robert Hale, 7s. 6d.) I looked at the title with amazement and then dived into it. ...