202 



LECTURE BY JOHN LANGTON ESQ. M.P.P. 



[1854. 



of astronomical observation was otherwise sufficiently advanced, to re- 

 cognise the tact that all the heavenly bodies move in conic sections, of 

 which discovery Newton's law of universal gravitation, with all its im- 

 portant consequences, was the immediate offspring. 



There are hundreds of similar facts to be met with in the history of 

 science. Yet people still continue to laugh at the apparently trifling 

 and useless researches of philosophers ! As Swift, in the voyage to 

 Laputa, satirized the contemporaries of Newton, Peter Pindar quizzed 

 those of Watt. Hook's pendulum experiments, in which the measure 

 of the earth originated, were ridiculed under the name of swing-swangs, 

 and Boyle's observations on the elasticity of air, one of the steps towards 

 the steam engine, were the objects of contemptuous sneers. The steam 

 engine itself, the mighty power of the nineteenth century, was, in its 

 first germs, little better than a scientific toy. What, indeed, could 

 appear more useless than experiments consisting of rubbing pieces of 

 amber, or sealing wax, or glass, and remarking the manner in which 

 they attract little straws, or bits of paper ? Yet in these the science 

 of electricity took its rise. Even when Franklin had to some extent 

 advanced the study, his practical countrymen thought it but learned 

 trifling, and asked, "What is the use of it?" Franklin answered, 

 " What is the use of a new-born baby ?" When we look at the electric 

 telegraph extending its wires all over the globe, and the countless ap- 

 plications of electricity to almost every branch of science and art, we 

 may well exclaim that that baby has, in less than a century, expanded 

 into a full-grown man, whose use no one would dare to question. 



The whole history of science abounds in instances of great discoveries 

 founded upon the simplest observations, and mighty effects resulting 

 from unimportant properties of matter. Franklin had the true spirit 

 of an inductive philosopher ; he was always inquiring into something 

 or other. In a voyage across the Atlantic he was engaged, as usual, 

 in trying experiments, and, having no other present field of inquiry, 

 he kept dipping his thermometer into the sea as he proceeded. I dare 

 say the sailors and his fellow passengers laughed secretly at the philo- 

 sopher, but these experiments resulted in ascertaining the fact, that 

 the different ocean currents have very different temperatures, the great 

 Gulf stream being as much as 12° higher than the surrounding ocean, 

 and the thermometer is consequently now a most useful instrument in 

 helping the mariner to shape his proper course. 



A soap-boiler finds a peculiar corrosion in his boilers, and applies 

 to a chemist for an explanation. The chemist analyzes the refuse 

 formed by the corrosion, and discovers a new substance, which, from 

 its violet colour, he calls iodine, after a Greek word. He argues, that 

 it must have come there in some of the substances employed by the 

 soap-boiler, and finds it in the alkali which was used. He next traces 

 it in the marine plants from the ashes of which the alkali was extract- 

 ed, and finally he discovers it in sea water, and almost all marine sub- 

 stances, amongst which are sponges. A physician now remembers 

 that burnt sponge has long been a popular remedy for goitre (a swell- 

 ing of the neck, accompanied, in the worst cases, by a peculiar form 

 of idiocy, which is a common complaint in Switzerland, and other 

 mountainous countries), and he tries the effect of pure iodine. The 

 consequence is the discovery of an almost certain cure for this most 

 distressing and heretofore nearly intractable disorder. 



Antimony is a metal long known, and abundant enough in nature, 

 though of very limited use in the arts ; but it has a peculiar property, 

 which might easily escape notice, without a knowledge of which the 

 art of printing would never have attained its present perfection. You 

 know that all substances expand with heat and contract with cold ; 

 but this general rule has a very few partial exceptions. The most 

 conspicuous one is water, which follows the general rule in the shape 

 of steam, and as water it continues to follow it till cooled down to 391° 

 of the thermometer. Beyond that point, every additional degree of 

 cold expands the water instead of contracting it, till, having expe- 

 rienced another sudden expansion in the act of freezing, it continues 

 ever after, in the form of ice, to contract with cold and expand with 

 heat like other bodies. The consequences to us of this exception are 

 most important ; for, were it otherwise, water would begin freezing at 

 the bottom, and not on the surface, and no summer's sun could pene- 

 trate to thaw the ice once formed : every piece of water would become 

 a solid lump of ice, and the earth would be uninhabitable. It is not, 

 however, of water that I would speak, but of antimony, which is an- 

 other partial exception, increasing in dimensions like water in the act 

 of becoming solid from a melted state. Now, the types used in print- 

 ing must be cast: to form them by carving or punching would make 

 printing almost as expensive as wilting ; but if cast in any ordinary 

 metal, the fine lines of the mould would not be copied, and the impres- 

 sion would be coarse and indistinct. The addition of a little antimony 



to the lead, of which types are principally formed, makes the whole 

 expand as it becomes solid, sufficiently to force the metal into the 

 sharpest indentations of the die. 



But it is said by some that you may leave such studies to the pro- 

 fessionally learned, and that working men have no time for them ; or 

 if the nature of their occupation requires some knowledge of scientific 

 results, it is sufficient for the mechanic to know the facts, and to work 

 upon the rules which the philosophers have laid down for him. It has 

 even been contended that the true principle of division of labour requires 

 that the philosopher should devote himself to perfecting theory, and 

 that the practical mechanic should confine his attention to attaining 

 mere manual dexterity. To a certain extent this division must neces- 

 sarily prevail, but if we are to look for much improvement in our pre- 

 sent process, or much advance in our actual knowledge, the two branches 

 must also be in a great measure combined. Theory and practice, as I 

 have said before, mutually aid each other, and the mechanic cannot 

 hope to attain much eminence without some theoretical knowledge, 

 whilst the theorist must not disdain the aid of practical experience. 

 The working mechanic, it is true, can but rarely become an accom- 

 plished philosopher, but he can, at any rate, become familiar with the 

 principles of those sciences more immediately connected with his pur- 

 suits ; and such is the mutual dependence of all the sciences, that he 

 should at least have some idea of the general bearing and extent of our 

 whole physical knowledge. A mere acquaintance with rules is not 

 enough ; for a man can never thoroughly understand, or even remem- 

 ber a rule, unless he knows something of the reason of it, and if he 

 comes to apply it under slightly altered circumstances, he can never 

 be certain that it continues to hold good for the-.case he has in hand. 

 How many persons have wasted great mechanical ingenuity in attempt- 

 ing perpetual motion, which a slight acquaintance with first principles 

 would have shown to be impossible ! How many thousands have been 

 thrown away in sinking shafts for coal, in strata which any geologist 

 knew beforehand could contain none, or in working imaginary gold 

 mines for what a mineralogist would, at a glance, have pronounced 

 to be only mica ! Again: if the object sought is possible, science will 

 guide you in ascertaining whether the means used are sufficient for the 

 purpose, or are the easiest, and most direct and economical, which 

 can be employed. But more than all, theory will often suggest, and 

 invite to a new track, which never would have occurred to a person 

 unacquainted with science. In a word, if you are content to go on 

 doing what preceding generations have done, you may perhaps trust 

 to experience and rules alone ; but if you wish to attempt anything 

 new, where you can have no guidance from experience or rule, you 

 must recur to first principles, which it is the province of science to 

 teach. 



Human nature is so prone to cavil, and it is so true a saying, that a 

 prophet has no honor in his own country, that I can imagine some of 

 my hearers may say (or if they do not like to say it openly, may secretly 

 think) that this would be all very well, if any of us were likely to make 

 new discoveries, or hit upon great inventions, but that it is so impro- 

 bable that the mechanics of a small village like Peterborough should 

 be going so to distinguish themselves, that it is hardly worth while to 

 make preparation for it. Perhaps we may have no undiscovered 

 geniuses amongst us ; but (not to mention that already one of our 

 fellow-townsmen has produced an invention, not yet thoroughly tested, 

 but which is now engaging the attention of persons in England, able 

 and willing to give it a fair trial) we never can know whether we have 

 them or not till it is proved by the event. Hundreds of inventions 

 have been made by simple mechanics, having no greater advantages 

 than many of you, whose achievements would tempt me to lay before 

 you some examples, were we not promised a lecture upon this subject 

 by my friend, Mr. Geniley. But not to mention names of such world- 

 wide reputation as Franklin, Watt, Arkwright, Godfrey, Dolland, Ste- 

 phenson, consider the numbers who, as improvers rather than invent- 

 ors, are daily benefiting mankind, and laying the foundation of their 

 own fortunes, without their names ever becoming known to fame. If 

 there is only one of you, or one of your children, who has within him 

 the hitherto undiscovered talent to contribute something new to science 

 or to art, we should be sufficiently rewarded for all our exertions to 

 enable him to acquire that knowledge, without which no opportunity, 

 no ingenuity, no natural talent can be of any avail. 



But if no practical mechanic can take full advantage of all the cir- 

 cumstances in which he is placed unless he have also some theoretical 

 knowledge, neither can a mere theorist ever effect much who has not 

 sufficient practical experience to know in what direction there is the 

 greatest room for improvement, and what are the existing means for 

 carrying it into effect. Almost all great discoveries and inventions 

 have been made by men who united theoretical to practical knowledge. 



