SEARCHING FOR WE KNOW NOT WHAT, AND FINDING IT. 239 of considerable heat. This was the origin of the so-called 'explosive antimony.' I subsequently investigated the phenomenon, and found that by slightly scratching a thick piece of the substance, the temperature it suddenly acquired was sometimes nearly as high as 700° F. In a similar manner, by subjecting a large number of substances in succession to contact with liquefied anhydrous hydrochloric acid under very great pressure, I discovered the singular circumstance that by contact of a porous piece of caustic lime with that liquid, contrary to expectation, the two bodies did not chemically combine, and therefore that neither water nor chloride of calcium was formed. From these various considerations and instances, it is evident that the most unexpected discovery, or even a discovery contrary to expectation, made by a scientific man, is usually a result of definite search, and that the term 'accidental' is in nearly all cases not strictly applicable to the discoveries made by scientific investigators. ' See Transactions of the Royal Society, 1857-58, and 1862. 240 PART III. PERSONAL PREPARATION FOR RESEARCH. CHAPTER XXVII. PERSONAL CONDITIONS OF SUCCESS IN RESEARCH. Who are the great? Those who have boldly ventured to explore These are the nobly great.-PRINCE. THE discovery of important scientific truths is an act more nearly allied than any other to that of creation; even the ancients recognised this, and classed great discoverers (and even inventors) with the gods. It is not usually the most PERSONAL QUALIFICATIONS FOR DISCOVERY. 241 public or the most popular scientific man, nor he who is apparently the most useful, who makes the greatest discoveries, but the less known and the less appreciated profound thinker and industrious original worker. A man's real ability in science is much less to be measured by his physical feats than by his intellectual ones; and also much less by the popularity accorded to him during his life by partially scientific persons, than by the honour assigned to him by succeeding scientific philosophers. The glory of Newton and of Faraday has far outshone that of the most popular expositor of science. A discoverer alone can best describe the mental conditions essential to successful research, or by which discoveries are made, because he alone can best realise the mental process passed through. But even he can only do it imperfectly, because of the difficulty experienced by the mind in observing its own actions. In discovering, much of the success depends upon the man. The greatest discoveries require a gifted and an active mind acutely impressible by the slightest really exceptional circumstance. The personal qualifications for achieving success in physical and chemical research are various; the most important are, an inherent sensitiveness to particular impressions of similarity and difference, an ardent spirit of enquiry and enterprise, suitable and sufficient knowledge of science, strong scientific imagination and fertile invention, acute observing faculties, accurate reasoning power, and aptitude in making experiments. A discoverer must be able to imagine hypotheses, invent means of testing them, manipulate in experiments, and infer causes and explanations. The humble faculties of indomitable industry, patience, and perseverance are constantly required to perform the drudging portion of searching for new truths; the faculties of imagination and invention are frequently R strained to a high degree in conceiving new hypotheses and devising means of testing them; and the logical or reasoning power is continually employed in explaining phenomena and in tracing connections between them. Some investigators are great in making experiments or observations, others in raising hypotheses, some in successfully predicting new results, and so on. Priestley made a great number of experiments. Tycho-Brahe made an immense number of accurate observations; Kepler was full of wild and fanciful hypotheses; Sir J. Herschel was unusually successful in predicting important new results. In some scientific discoverers the logical and not the mathematical faculty is largely developed; Faraday was an example of this; in others, both are combined. The most common defects in scientific investigators are want of perseverance and industry in experiments, and deficient ability in discerning true explanations. As there is no royal road to learning, neither is there an easy path to the discovery of great scientific truths. It needs a much greater degree of mental power to discover new scientific knowledge than to acquire and communicate that which is known. Clearness of ideas is one great condition of success in scientific discovery, but the ideas must not only be clear but also be suitable. 'The operations of the mind as well as the information of the senses, ideas as well as facts, are requisite for the attainment of any knowledge; and all great discoveries in science require a peculiar distinctness and vividness of thought in the discoverer. This it is difficult to exemplify in any better way than by the discoverers themselves. Both Davy and Faraday possessed this vividness of mind; and it was a consequence of this endowment that Davy's lectures upon chemistry, and Faraday's upon almost any subject of physical philo DEFINITIONS OF SCIENTIFIC GENIUS. 243 sophy, were of the most brilliant and captivating character. In discovering the nature of voltaic action, the essential intellectual requisite was to have a distinct conception of that which Faraday expressed by the remarkable phrase, "An axis of power having equal and opposite forces." And the distinctness of this idea in Faraday's mind shines forth in every part of his writings.' 'He appears to possess the idea of this kind of force with the same eminent distinctness with which Archimedes in the ancient and Stevinus in the modern history of science possessed the idea of pressure, and were thus able to found the idea of mechanics. And when he cannot obtain these distinct modes of conception, he is dissatisfied, and conscious of defect.'1 The mental faculties of great scientific discoverers, though more penetrating, truthful, and accurate than those of men in general, are limited by the same general conditions. Many of those who have made very great discoveries have laboured under the imperfection of thought which was the obstacle to the next step in knowledge. Though Kepler detected, with great acuteness, the numerical laws of the solar system, he laboured in vain to conceive the very simplest of the laws of motion by which the paths of the planets are governed. Though Priestley made some important steps in chemistry, he could not bring his mind to admit the doctrine of a general principle of oxidation.' To err in this way is the lot not only of men in general, but of men of great endowments, and very sincere love of truth.' 2 Buffon said that scientific genius is only protracted patience.' Cuvier said: 'In the exact sciences at least, it is the patience of a sound intellect, when invincible, 1 Whewell, History of Inductive Sciences, vol. iii. 3rd ed., p. 147. 2 Whewell, Philosophy of the Inductive Sciences, vol. ii. p. 175. |