But having done those, Daniel picked up the tangents paper, shook off the black grit that re-punctuated it, and headed out the door. This was no more than a tenth of everything Isaac had accomplished with fluxions, but it was at least a shred of evidence – better than nothing – and sufficient to keep most Fellows of the Royal Society in bed with headaches for weeks. The night overhead was clear, the view excellent, the mysteries of the Universe all spread out above Trinity College. But Daniel lowered his sights and plodded toward the cone of steamy light where everyone was waiting.