Engraving taken from 'Experiments Upon Vegetables, discovering their great power of purifying the common air in the sunshine, and of injuring it in the shade and at night' by Jan Ingenhousz, published in London in 1779. Ingenhousz (1730-1799), was a Dutch scientist working in England, who discovered that carbon dioxide is absorbed by plants in the day and given out at night. He also demonstrated photosynthesis, conducted over 500 experiments and wrote up his findings in 'Experiments Upon Vegetables...'. He later became surgeon to the Austrian royal family, inoculating them against smallpox using Edward Jenner's (1749-1823) method.
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