Macbeth's metaphor, in his utterance if th'assassination / Could trammel up the consequence, and catch, / With his surcease, success (1.7.24), is not quite clear. Is the image taken from fishing, or horse hobbling, or bird catching? And what does the 'up' stand for? A passage from Gervase Markham's treatise Hungers Preuention: Or, The whole Arte Of Fowling By Water and Land (London, 1621) helps to elucidate the passage as a metaphor drawn from fowling. Gervase Markham (ca. 1568-1637) was a hack writer, scholar, poet, dramatist, and expert in agriculture and horse-breeding who has been linked with Shakespeare's Don Armado and the rival poet of the sonnets.1 In the chapter in question, Markham describes a special way of fowling with the help of a trammel net. This is a large rectangular net with at least two layers of meshes of different sizes. It is held up in two corners by several men and trailed along the ground, its lower end kept down by lead plummets. This is done by night, on unenclosed ground and in open fields, called champion or champaigne (grass, heather, stubble fields, fallow land, etc.). Other men walk beside the net, with lights and torches, carrying long poles. The birds press closely to their cover at first. When the party approaches, some try to run away, but the lights keep them toward the middle. There they are put up by the poles and become entangled in the trammel. Those birds that manage to escape, scatter and hide and can no longer be taken in one catch. The birds stalked are, in Markham's words, Partriges, Rayles, Larkes, Quailes, or any other small Birdes of