As Master of the Mint, Newton could have claimed whatever space he’d taken a whim to. But he’d always been a most practical Master, keen to better the productivity of the place, and so he had situated his personal atelier so as not to impede the coiners’ work. It was about forty feet on a side, divided into several closets, a wee chamber that communicated with the interior of Brick Tower and thence to the Inner Ward, and a single great laboratory-cum-office that commanded a view up, and down, and across this leg of Mint Street. Scarlet late-afternoon sun was angling in through rents in northwestern clouds, setting White’s left cheek and shoulder aglow, but only because they were elevated above the ground here; below them, Mint Street had already fallen into twilight, being over-shadowed by the glum row of casemates that lined the near surface of the outer wall. The casemate situated across from Newton’s laboratory and a bit off to the right was at once the best and the worst of these. Its sole practical function, lately, had been to enclose the Vault that housed the Pyx. As such it had been guarded round the clock by men identifying themselves as Queen’s, and more recently King’s, Messengers. Which amounted to that they wore silver-greyhound badges and had bits of paper bearing the signature and the seal of Charles White.