1157. The importance of mineral substances to plants was not formerly generally known, as, before Liebig promulgated his discoveries, it was supposed by most vegetable physiologists that the mineral substances which were occasionally found in plants in minute quantities, 'were accidental and unimportant.' It is worthy of remark, however, that Dr. Lindley appears to have been aware of the absolute necessity which plants had for mineral substances in their food, before the fact was generally acknowledged; as, in his Theory of Horticulture, published before Liebig's great work, he observes, 'that where mineral substances occur abundantly in plants, they we part and parcel of their nature, just as much as iron and phosphate of lime are of our own bodies; and we must no more suppose that grasses can dispense with silica in their food, or marine plants with common salt, than that we ourselves could dispense with vegetable and animal food.' (Theory of Horticulture, p. 356.)
