and deliberately in coloured chalks a diagram for the class to copy in coloured pencils, and sometimes he would display a specimen or arrange an experiment for them to see. The room in the Institute in which he taught was equipped with a certain amount of apparatus prescribed as necessary for subject this and subject that by the Science and Art Department, and this my father would supplement with maps and diagrams and drawings of his own.
But he never really did experiments, except that in the class in systematic botany he sometimes made us tease common flowers to pieces. He did not do experiments if he could possibly help it, because in the first place they used up time and gas for the Bunsen burner and good material in a ruinous fashion, and in the second they were, in his rather careless and sketchy hands, apt to endanger the apparatus of the Institute and even the lives of his students. Then thirdly, real experiments involved washing up. And moreover they always turned out wrong, and sometimes misled the too observant learner very seriously and opened demoralising controversies. Quite early in life I acquired an almost ineradicable sense of the unscientific perversity of Nature and the impassable gulf that is fixed between systematic science and elusive fact. I knew, for example, that in science, whether it be subject XII., Organic Chemistry, or subject XVII., Animal Physiology, when you blow into a glass of lime-water it instantly becomes cloudy, and if you continue to blow it clears again, whereas in truth you may blow into the stuff from the lime-water bottle until you are crimson in the face and painful under the ears, and it never becomes cloudy at all. And I knew, too, that in science if you put potassium chlorate into a retort and heat it over a Bunsen burner, oxygen is disengaged and may be collected over water, whereas in real life if you do anything of the sort the vessel cracks with a loud report, the potassium chlorate descends sizzling upon the flame, the experimenter says "Oh! Damn!" with astonishing heartiness and distinctness, and a lady student in the back seats gets up and leaves the room.
Science is the organised conquest of Nature, and I can quite understand that ancient libertine refusing to co-operate in her own undoing. And I can quite understand, too, my father's preference for what he called an illustrative experiment, which was simply an arrangement of the apparatus in front of the class with nothing whatever by way of material, and the Bunsen burner clean and cool, and then a slow luminous description of just what you did put in it when you were so ill-advised as to carry the affair beyond illustration, and just exactly what ought anyhow to happen when you did. He had considerable powers of vivid expression, so that in this way he could make us see all he described. The class, freed from any unpleasant nervous tension, could draw this still life without flinching, and if any part was too difficult to draw, then my father would produce a simplified version on the blackboard to be copied instead. And he would also write on the blackboard any exceptionally difficult but grant-earning words, such as "empyreumatic" or "botryoidal."
Some words in constant use he rarely explained. I remember once sticking up my hand and asking him in the full flow of description, "Please, sir, what is flocculent?"
"The precipitate is."
"Yes, sir, but what does it mean?"
"Oh! flocculent!" said my father, "flocculent! Why--" he extended his hand and arm and twiddled his fingers for a second in the air. "Like that," he said.
I thought the explanation sufficient, but he paused for a moment after giving it. "As in a flock bed, you know," he added and resumed his discourse.
3
My father, I am afraid, carried a natural incompetence in practical affairs to an exceptionally high level. He combined practical incompetence, practical enterprise and a thoroughly sanguine temperament, in a manner that I have never seen paralleled in any human being. He was always trying to do new things in the briskest manner, under the suggestion of books or papers or his own spontaneous imagination, and as he had never been trained to do anything whatever in his life properly, his futilities were extensive and thorough. At one time he nearly gave up his classes for intensive culture, so enamoured was he of its possibilities; the peculiar pungency of the manure he got, in pursuit of a chemical theory of his own, has scarred my olfactory memories for a lifetime. The intensive culture phase is very clear in my memory; it came near the end of his career and when I was between eleven and twelve. I was mobilised to gather caterpillars on several occasions,
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