The Romance of Modern Chemistry

CHEMISTRY AND AGRICULTURE practice of the past and the knowledge of the new age is always recurring, and we are slow to learn the lesson that the science of the laboratory cannot in the long run be kept out of the field, the factory, the workshop, or even the kitchen. Suppose, then, we’ consider for a little what chemistry has to teach us about the growth and culture of the vegetable world, about the yearly marvel of wood and field and garden. For it is a marvel. Look at the fields in the time of sowing ; they are brown and bare and dead. Look at them five months later ; they are clothed with an abundant garment of living green or gold. In the interval no influence but that of soil and sun, of wind and rain, has played upon the seed and the growing plant. Whence, then, all this wealth of fresh material ? Is it a new creation, or is it an equally marvellous transformation ? If the latter, what are the substances which have been changed, as by a magician’s wand, into stem and leaf and flower ? Surprising as it may seem, it is only three hundred years ago since a chemist of repute endeavoured to show that vegetable substances were produced from water alone. The experiment by which he sought to prove this was a very simple one, and is worth rehearsal. The story shows how easy it is for any traveller into the unknown to miss the right path. This chemist took a willow weighing 5 pounds and planted it in a quantity of dried earth which weighed 200 pounds. For five years he did nothing to the willow except water it occasionally. At the end of that time it was pulled up and found to weigh 169 pounds 2 ounces. The earth in which the willow had grown was dried as before, and was found to be only 2 ounces lighter than at 216