In a Westerly Tour I made this year, amongst numerous other places I visited Blenheim, and made the following memorandum:—
‘Viewed the pleasure ground at Blenheim, the enclosed part of which consists of 200 acres, with the water near 300. It can scarcely be too much admired; the whole environ of the water is fine, various in its feature, with the character of magnificence everywhere impressed. The cascade scenery, viewed independently of the new improvements, is extremely pleasing, and indeed wants nothing but a deeper and more umbrageous shade for an accompaniment. The new walks, caves, fountains, and statues do not, however, seem entirely calculated to add to the beauty of the scenery. The most splendid view is from the walk leading from the cascade to the house. There are two points nearly similar, where are benches; the water fills the bottom of the vale in the style of a very noble river; few, indeed, in the kingdom exceed it. We may conjecture that if Brown, in the exultation of his heart, really said that the Thames would never pardon his superb imitation for exceeding the original, it was the view from one of these benches that inspired the sentiment. The proud waves that roll at your feet; the declivity steep enough to make the water and every contiguous scene more interesting to the eye; the opposite shore, a hill spread with wood that hangs with forest boldness to the water; the whole is formed to make an impression on the mind. No ill-judged decoration weakens by dividing the effect; no intruding objects hurt the simplicity of the scene. I know not any artificial scene that is finer. The concluding one where the water expands is great, but I think inferior to this. But to return——
[l.]
It appears this year[[109]] that I was engaged in a pursuit entirely new to me, that of making many new and pneumatic experiments on expelling gas from soils, manures, and various other substances, in order to ascertain whether there was any connection between the quantity and species of such gas (from Geist, German for ghost, spirit. Authority, B. of Llandaff, see Newman’s ‘Trans. of Boerhave’s Chemistry’) and the fertility of the soils from which my specimens were selected. It seems that I prosecuted this enquiry with diligence; and as it was my commencement in chemistry, I corresponded upon the subject with Dr. Priestley, and went to Cambridge for the conversation of Mr. Milner, then Professor of Chemistry in that University. The result of my experiments was very remarkable, for I decided, after a very careful deduction from the result of all my trials, that there existed a very intimate, and almost unbroken, connection between the fertility of land and the gas to be expelled from it. This was an entirely new discovery belonging to me only, and it has been quoted by many celebrated chemists in a manner which showed that they considered me as the origin of it. I sent a detail of my trials to the Royal Society, through the hands of Mr. Magellan,[[110]] as my paper contained some eudiometrical experiments made with the eudiometer invented by that philosopher. Mentioning to a friend what I had done, ‘You have been very foolish,’ observed the friend, ‘for depend upon it your paper will never get into the “Philosophical Transactions.”’ Expressing my surprise, I demanded the reason. ‘Why, know you not,’ he replied, ‘that there is a most inveterate hostility between Sir J. Banks and Magellan, from a violent quarrel, and Sir J. is not a man to permit anything to be printed that comes through hands offensive to him, especially as the paper is to the credit of Magellan’s instrument?’ The event proved the truth of this prediction, but this did not prevent my labours being duly appreciated by those who were the most competent judges. In the pursuit of these trials I gradually established and furnished a laboratory, sufficient for my own enquiries, at about 150l. expense.
l.
‘Birmingham: Jan. 27, 1783.
‘Dear Sir,—There is no person I should serve with more pleasure than you, because there is no person whose pursuits are more eminently useful to the world. You alone have certainly done more to promote agriculture, and especially to render it reputable, in this country than all that have gone before you. But the little I might do to aid your investigations will be reduced to a small matter indeed by my distance from you.
‘All that I should be able to do with water would be to expel by heat all the air it contains, and then examine, by nitrous air, how much phlogiston that air contains, but it is very possible that the fitness of water for irrigating meadows may depend upon something besides the phlogiston it contains. Experiment alone can determine these things. I never heard before of the inference, you say, has been drawn from my doctrine with respect to the use of light in vegetation. I know of no use that light is of to the soil. The whole effect is on the living plant, enabling it to convert the impure air it meets with in water or in the atmosphere into pure air. When that end is effected that water is of no further use to it. Plants will not thrive unless both their leaves and roots be exposed to air in some degrees impure. This I have fully ascertained, but I am afraid that the doctrine is not capable of much practical application.
‘I know of no method of conveying phlogiston to the roots of plants but as combined with water, and this seems to be done in the best way by a mixture of putrid matter. Water will not imbibe much inflammable air. I find volatile alkali to contain much phlogiston. It is indeed almost another modification of the same thing.
‘Since my last, I have hit upon various methods of converting water into permanent air. It is sufficient to give it something more than a boiling heat. If I only put an ounce of water into a porous earthen retort, I get a hundred ounce measures of air from it, and when I have, in this manner, got near an ounce weight of air from the same retort, it has not weighed one grain less than it did.