Boxtel heard him give the order, and saw the sentry-box put up that very day; but he deemed himself lucky in not having been suspected, and, being more than ever incensed against the successful horticulturist, he resolved to bide his time.

Just then the Tulip Society of Haarlem offered a prize for the production of the large black tulip without a spot of colour, a thing which had not yet been accomplished, and was considered impossible, as at that time there did not exist a flower of that species approaching even to dark-nut-brown. It was, therefore, generally said that the founders of the prize might just as well have offered two millions as a hundred thousand guilders, since no one would be able to gain it.

The tulip-growing world, however, was thrown by it into a state of most active commotion. Some fanciers caught at the idea without believing it practicable; but such is the power of imagination among florists, that, although considering the undertaking as certain to fail, all their thoughts were engrossed by that grand black tulip, which was looked upon as chimerical, as the black swan or the white raven were reputed to be in those days.

Van Baerle was one of the tulip-growers who were struck with the idea; Boxtel thought of it in the light of a speculation. Van Baerle, as soon as the idea had once taken root in his clear and ingenious mind, began slowly the necessary sowings and operations to reduce the tulips, which he had grown already, from red to brown, and from brown to dark brown.

By the next year he had obtained flowers of a perfect nut-brown, and Boxtel espied them in the border, whereas he had himself, as yet, only succeeded in producing the light brown.

Boxtel, once more worsted by the superiority of his hated rival, was now completely disgusted with tulip-growing, and, being driven half mad, devoted himself entirely to observation.

The house of his rival was quite open to view: a garden exposed to the sun; cabinets with glass walls, shelves, cupboards, boxes and ticketed pigeon-holes, which could easily be surveyed by the telescope. Boxte allowed his bulbs to rot in the pits, his seedlings to dry up in their cases, and his tulips to wither in the borders, and henceforward occupied himself with nothing else but the doings at Van Baerle’s.

But the most curious part of the operations was not performed in the garden.

It might be one o’clock in the morning, when Van Baerle went up to his laboratory, into the glazed cabinet whither Boxtel’s telescope had such easy access; and here, as soon as the lamp illuminated the walls and windows, Boxtel saw the inventive genius of his rival at work.

He beheld him sifting his seeds, and soaking them in liquids which were destined to modify or to deepen their colours. He knew what Cornelius meant, when, heating certain grains, then moistening them, then combining them with others by a sort of grafting-a minute and marvellously-delicate manipulation—he shut up in darkness those which were expected to furnish the black colour; exposed to the sun or to the lamp those which were to produce red; and placed between the endless reflection of two water-mirrors those intended for white, the pure representation of the limpid element.

This innocent magic, the fruit at the same time of childlike musings and of manly genius—this patient untiring labour, of which Boxtel knew himself to be incapable—made him, gnawed as he was with envy, centre all his life, all his thoughts, and all his hopes, in his telescope.