DIALOGUE THE FIFTH. THE CHEMICAL PHILOSOPHER.

I had been made religious by the conversations of Ambrosio in Italy; my faith was strengthened and exalted by the opinions of the Unknown, for whom I had not merely that veneration awakened by exalted talents, but a strong affection founded upon the essential benefit of the preservation of my life owing to him. I ventured, the evening after our visit to the cave of Adelsberg, to ask him some questions relating to his history and adventures. He said, “To attempt to give you any idea of the formation of my character would lead me into the history of my youth, which almost approaches to a tale of romance. The source of the little information and intelligence I possess I must refer to a restless activity of spirit, a love of glory which ever belonged to my infancy, and a sensibility easily excited and not easily conquered. My parentage was humble, yet I can believe a traditional history of my paternal grandmother, that the origin of our family was from an old Norman stock; I found this belief upon certain feelings which I can only refer to an hereditary source, a pride of decorum, a tact and refinement even in boyhood, and which are contradictory to the idea of an origin from a race of peasants. Accident opened to me in early youth a philosophical career, which I pursued with success. In manhood fortune smiled upon me and made me independent; I then really became a philosopher, and pursued my travels with the object of instructing myself and of benefiting mankind. I have seen most parts of Europe, and conversed, I believe, with all the illustrious men of science belonging to them. My life has not been unlike that of the ancient Greek sages. I have added some little to the quantity of human knowledge, and I have endeavoured to add something to the quantity of human happiness. In my early life I was a sceptic; I have informed you how I became a believer, and I constantly bless the Supreme Intelligence for the favour of some gleams of Divine light which have been vouchsafed to me in this our state of darkness and doubt.”

Phil.—I am surprised that with your powers you did not enter into a professional career either of law or politics; you would have gained the highest honours and distinctions.

The Unknown.—To me there never has been a higher source of honour or distinction than that connected with advances in science. I have not possessed enough of the eagle in my character to make a direct flight to the loftiest altitudes in the social world, and I certainly never endeavoured to reach those heights by using the creeping powers of the reptile who, in ascending, generally chooses the dirtiest path, because it is the easiest.

Eub.—I have often wondered that men of fortune and of rank do not apply themselves more to philosophical pursuits; they offer a delightful and enviable road to distinction, one founded upon the blessings and benefits conferred on our fellow-creatures; they do not supply the same sources of temporary popularity as successes in the senate or at the bar, but the glory resulting from them is permanent and independent of vulgar taste or caprice. In looking back to the history of the last five reigns in England, we find Boyles, Cavendishes, and Howards, who rendered those great names more illustrious by their scientific honours; but we may in vain search the aristocracy now for philosophers, and there are very few persons who pursue science with true dignity; it is followed more as connected with objects of profit than those of fame, and there are fifty persons who take out patents for supposed inventions for one who makes a real discovery.

Phil.—The information we have already received from you proves to me that chemistry has been your favourite pursuit. I am surprised at this. The higher-mathematics and pure physics appear to me to offer much more noble objects of contemplation and fields of discovery, and, practically considered, the results of the chemist are much more humble, belonging principally to the apothecary’s shop and the kitchen.

Eub.—I feel disposed to join you in attacking this favourite study of our friend, but merely to provoke him to defend it. I wish our attack would induce him to vindicate his science, and that we might enjoy a little of the sport of literary gladiators, at least, in order to call forth his skill and awaken his eloquence.

The Unknown.—I have no objection. Let there be a fair discussion; remember we fight only with foils, and the point of mine shall be covered with velvet. In your attack upon chemistry, Philalethes, you limited the use of it to the apothecary’s shop and the kitchen. The first is an equivocal use; by introducing it into the kitchen you make it an art fundamental to all others. But if what you had stated had really meant to be serious, it would not have deserved a reply; as it is in mere playfulness, it shall not be thrown away. I want eloquence, however, to adorn my subject, yet it is sufficiently exciting even to awaken feeling. Persons in general look at the magnificent fabric of civilized society as the result of the accumulated labour, ingenuity, and enterprise of man through a long course of ages, without attempting to define what has been owing to the different branches of human industry and science; and usually attribute to politicians, statesmen, and warriors a much greater share than really belongs to them in the work: what they have done is in reality little. The beginning of civilization is the discovery of some useful arts by which men acquire property, comforts, or luxuries. The necessity or desire of preserving them leads to laws and social institutions. The discovery of peculiar arts gives superiority to particular nations; and the love of power induces them to employ this superiority to subjugate other nations, who learn their arts, and ultimately adopt their manners; so that in reality the origin, as well as the progress and improvement, of civil society is founded in mechanical and chemical inventions. No people have ever arrived at any degree of perfection in their institutions who have not possessed in a high degree the useful and refined arts. The comparison of savage and civilized man, in fact, demonstrates the triumph of chemical and mechanical philosophy as the causes not only of the physical, but ultimately even of moral improvement. Look at the condition of man in the lowest state in which we are acquainted with him. Take the native of New Holland, advanced only a few steps above the animal creation, and that principally by the use of fire; naked, defending himself against wild beasts or killing them for food only by weapons made of wood hardened in the fire, or pointed with stones or fish bones; living only in holes dug out of the earth, or in huts rudely constructed of a few branches of trees covered with grass; having no approach to the enjoyment of luxuries or even comforts; unable to provide for his most pressing wants; having a language scarcely articulate, relating only to the great objects of nature, or to his most pressing necessities or desires, and living solitary or in single families, unacquainted with religion, government, or laws, submitted to the mercy of nature or the elements. How different is man in his highest state of cultivation; every part of his body covered with the products of different chemical and mechanical arts made not only useful in protecting him from the inclemency of the seasons but combined in forms of beauty and variety; creating out of the dust of the earth from the clay under his feet instruments of use and ornament; extracting metals from the rude ore and giving to them a hundred different shapes for a thousand different purposes; selecting and improving the vegetable productions with which he covers the earth; not only subduing but taming and domesticating the wildest, the fleetest, and the strongest inhabitants of the wood, the mountain, and the air; making the winds carry him on every part of the immense ocean; and compelling the elements of air, water, and even fire as it were to labour for him; concentrating in small space materials which act as the thunderbolt, and directing their energies so as to destroy at immense distances; blasting the rock, removing the mountain, carrying water from the valley to the hill; perpetuating thought in imperishable words, rendering immortal the exertion of genius, and presenting them as common property to all awakening minds, becoming as it were the true image of divine intelligence receiving and bestowing the breath of life in the influence of civilization.

Eub.—Really you are in the poetical, not the chemical chair, or rather on the tripod. We claim from you some accuracy of detail, some minute information, some proofs of what you assert. What you attribute to the chemical and mechanical arts, we might with the same propriety attribute to the fine arts, to letters, to political improvement, and to those inventions of which Minerva and Apollo and not Vulcan are the patrons.

The Unknown.—I will be more minute. You will allow that the rendering skins insoluble in water by combining with them the astringent principle of certain vegetables is a chemical invention, and that without leather, our shoes, our carriages, our equipages would be very ill made; you will permit me to say, that the bleaching and dying of wool and silk, cotton, and flax, are chemical processes, and that the conversion of them into different clothes is a mechanical invention; that the working of iron, copper, tin, and lead, and the other metals, and the combining them in different alloys by which almost all the instruments necessary for the turner, the joiner, the stone-mason, the ship-builder, and the smith are made, are chemical inventions; even the press, to the influence of which I am disposed to attribute as much as you can do, could not have existed in any state of perfection without a metallic alloy; the combining of alkali and sand, and certain clays and flints together to form glass and porcelain is a chemical process; the colours which the artist employs to frame resemblances of natural objects, or to create combinations more beautiful than ever existed in Nature, are derived from chemistry; in short, in every branch of the common and fine arts, in every department of human industry, the influence of this science is felt, and we may find in the fable of Prometheus taking the flame from heaven to animate his man of clay an emblem of the effects of fire in its application to chemical purposes in creating the activity and almost the life of civil society.

Phil.—It appears to me that you attribute to science what in many cases has been the result of accident. The processes of most of the useful arts, which you call chemical, have been invented and improved without any refined views, without any general system of knowledge. Lucretius attributes to accident the discovery of the fusion of the metals; a person in touching a shell-fish observes that it emits a purple liquid as a dye, hence the Tyrian purple; clay is observed to harden in the fire, and hence the invention of bricks, which could hardly fail ultimately to lead to the discovery of porcelain; oven glass, the most perfect and beautiful of those manufactures you call chemical, is said to have been discovered by accident; Theophrastus states that some merchants who were cooking on lumps of soda or natron, near the mouth of the river Belus, observed that a hard and vitreous substance was formed where the fused natron ran into the sand.

The Unknown.—I will readily allow that accident has had much to do with the origin of the arts as with the progress of the sciences. But it has been by scientific processes and experiments that these accidental results have been rendered really applicable to the purposes of common life. Besides, it requires a certain degree of knowledge and scientific combination to understand and seize upon the facts which have originated in accident. It is certain that in all fires alkaline substances and sand are fused together, and clay hardened; yet for ages after this discovery of fire, glass and porcelain were unknown till some men of genius profited by scientific combination often observed but never applied. It suits the indolence of those minds which never attempt anything, and which probably if they did attempt anything would not succeed, to refer to accident that which belongs to genius. It is sometimes said by such persons, that the discovery of the law of gravitation was owing to accident: and a ridiculous story is told of the falling of an apple as the cause of this discovery. As well might the invention of fluxions or the architectural wonders of the dome of St. Peter’s, or the miracles of art the St. John of Raphael or the Apollo Belvidere, be supposed to be owing to accidental combinations. In the progress of an art, from its rudest to its more perfect state, the whole process depends upon experiments. Science is in fact nothing more than the refinement of common sense making use of facts already known to acquire new facts. Clays which are yellow are known to burn red; calcareous earth renders flint fusible—the persons who have improved earthenware made their selections accordingly. Iron was discovered at least one thousand years before it was rendered malleable; and from what Herodotus says of this discovery, there can be little doubt that it was developed by a scientific worker in metals. Vitruvius tells us that the ceruleum, a colour made of copper, which exists in perfection in all the old paintings of the Greeks and Romans and on the mummies of the Egyptians, was discovered by an Egyptian king; there is therefore every reason to believe that it was not the result of accidental combination, but of experiments made for producing or improving colours. Amongst the ancient philosophers, many discoveries are attributed to Democritus and Anaxagoras; and, connected with chemical arts, the narrative of the inventions of Archimedes alone, by Plutarch, would seem to show how great is the effect of science in creating power. In modern times, the refining of sugar, the preparation of nitre, the manufacturing of acids, salts, &c., are all results of pure chemistry. Take gunpowder as a specimen; no person but a man infinitely diversifying his processes and guided by analogy could have made such a discovery. Look into the books of the alchemists, and some idea may be formed of the effects of experiments. It is true, these persons were guided by false views, yet they made most useful researches; and Lord Bacon has justly compared them to the husbandman who, searching for an imaginary treasure, fertilised the soil. They might likewise be compared to persons who, looking for gold, discover the fragments of beautiful statues, which separately are of no value, and which appear of little value to the persons who found them; but which, when selected and put together by artists and their defective parts supplied, are found to be wonderfully perfect and worthy of conservation. Look to the progress of the arts since they have been enlightened by a system of science, and observe with what rapidity they have advanced. Again, the steam-engine in its rudest form was the result of a chemical experiment; in its refined state it required the combinations of all the most recondite principles of chemistry and mechanics, and that excellent philosopher who has given this wonderful instrument of power to civil society was led to the great improvements he made by the discoveries of a kindred genius on the heat absorbed when water becomes steam, and of the heat evolved when steam becomes water. Even the most superficial observer must allow in this case a triumph of science, for what a wonderful impulse has this invention given to the progress of the arts and manufactories in our country, how much has it diminished labour, how much has it increased the real strength of the country! Acting as it were with a thousand hands, it has multiplied our active population; and receiving its elements of activity from the bowels of the earth, it performs operations which formerly were painful, oppressive, and unhealthy to the labourers, with regularity and constancy, and gives security and precision to the efforts of the manufacturer. And the inventions connected with the steam-engine, at the same time that they have greatly diminished labour of body, have tended to increase power of mind and intellectual resources. Adam Smith well observes that manufacturers are always more ingenious than husbandmen; and manufacturers who use machinery will probably always be found more ingenious than handicraft manufacturers. You spoke of porcelain as a result of accident; the improvements invented in this country, as well as those made in Germany and France, have been entirely the result of chemical experiments; the Dresden and the Sevres manufactories have been the work of men of science, and it was by multiplying his chemical researches that Wedgewood was enabled to produce at so cheap a rate those beautiful imitations which while they surpass the ancient vases in solidity and perfection of material, equal them in elegance, variety, and tasteful arrangement of their forms. In another department, the use of the electrical conductor was a pure scientific combination, and the sublimity of the discovery of the American philosopher was only equalled by the happy application he immediately made of it. In our own times it would be easy to point out numerous instances in which great improvements and beneficial results connected with the comforts, the happiness, and even life of our fellow creatures have been the results of scientific combinations; but I cannot do this without constituting myself a judge of the works of philosophers who are still alive, whose researches are known, whose labours are respected, and who will receive from posterity praises that their contemporaries hardly dare to bestow upon them.

Eub.—We will allow that you have shown in many cases the utility of scientific investigation as connected with the progress of the useful arts. But, in general, both the principles of chemistry are followed, and series of experiments performed without any view to utility; and a great noise is made if a new metal or a new substance is discovered, or if some abstracted law is made known relating to the phenomena of nature; yet, amongst the variety of new substances, few have been applied to any trifling use even, and the greater number have had no application at all. And with respect to the general views of the science, it would be difficult to show that any real good had resulted from the discovery or extension of them. It does not add much to the dignity of a pursuit that those persons who have followed it for profit have really been most useful, and that the mere artisan or chemical manufacturer has done more for society than the chemical philosopher. Besides, it has always appeared to me that it is in the nature of this science to encourage mediocrity and to attach importance to insignificant things; very slight chemical labours seem to give persons a claim to the title of philosopher—to have dissolved a few grains of chalk in an acid, to have shown that a very useless stone contains certain known ingredients, or that the colouring matter of a flower is soluble in acid and not in alkali, is thought by some a foundation for chemical celebrity. I once began to attend a course of chemical lectures and to read the journals containing the ephemeral productions of this science; I was dissatisfied with the nature of the evidence which the professor adopted in his demonstrations, and disgusted with the series of observations and experiments which were brought forward one month to be overturned the next. In November there was a Zingeberic acid, which in January was shown to have no existence; one year there was a vegetable acid, which the next was shown to be the same as an acid known thirty years ago; to-day a man was celebrated for having discovered a new metal or a new alkali, and they flourished like the scenes in a new pantomime only to disappear. Then, the great object of the hundred triflers in the science appeared to be to destroy the reputation of the three or four great men whose labours were really useful, and had in them something of dignity. And, there not being enough of trifling results or false experiments to fill up the pages of the monthly journals, the deficiency was supplied by some crude theories or speculations of unknown persons, or by some ill-judged censure or partial praise of the editor.

The Unknown.—I deny in toto the accuracy of what you are advancing. I have already shown that real philosophers, not labouring for profit, have done much by their own inventions for the useful arts; and, amongst the new substances discovered, many have had immediate and very important applications. The chlorine, or oxymuriatic gas of Scheele, was scarcely known before it was applied by Berthollet to bleaching; scarcely was muriatic acid gas discovered by Priestley, when Guyton de Morveau used it for destroying contagion. Consider the varied and diversified applications of platinum, which has owed its existence as a useful metal entirely to the labours of an illustrious chemical philosopher; look at the beautiful yellow afforded by one of the new metals, chrome; consider the medical effects of iodine in some of the most painful and disgusting maladies belonging to human nature, and remember how short a time investigations have been made for applying the new substances. Besides, the mechanical or chemical manufacturer has rarely discovered anything; he has merely applied what the philosopher has made known, he has merely worked upon the materials furnished to him. We have no history of the manner in which iron was rendered malleable; but we know that platinum could only have been worked by a person of the most refined chemical resources, who made multiplied experiments upon it after the most ingenious and profound views. But, waiving all common utility, all vulgar applications, there is something in knowing and understanding the operation of Nature, some pleasure in contemplating the order and harmony of the arrangements belonging to the terrestrial system of things. There is no absolute utility in poetry, but it gives pleasure, refines and exalts the mind. Philosophic pursuits have likewise a noble and independent use of this kind, and there is a double reason offered for pursuing them, for whilst in their sublime speculations they reach to the heavens, in their application they belong to the earth; whilst they exalt the intellect, they provide food for our common wants, and likewise minister to the noblest appetites and most exalted views belonging to our nature. The results of this science are not like the temples of the ancients, in which statues of the gods were placed, where incense was offered and sacrifices were performed, and which were presented to the adoration of the multitude founded upon superstitious feelings; but they are rather like the palaces of the moderns, to be admired and used, and where the statues, which in the ancients raised feelings of adoration and awe, now produce only feelings of pleasure, and gratify a refined taste. It is surely a pure delight to know how and by what processes this earth is clothed with verdure and life, how the clouds, mists, and rain are formed, what causes all the changes of this terrestrial system of things, and by what divine laws order is preserved amidst apparent confusion. It is a sublime occupation to investigate the cause of the tempest and the volcano, and to point out their use in the economy of things, to bring the lightning from the clouds and make it subservient to our experiments, to produce, as it were, a microcosm in the laboratory of art, and to measure and weigh those invisible atoms which, by their motions and changes according to laws impressed upon them by the Divine Intelligence, constitute the universe of things. The true chemical philosopher sees good in all the diversified forms of the external world. Whilst he investigates the operations of infinite power guided by infinite wisdom, all low prejudices, all mean superstitions, disappear from his mind. He sees man an atom amidst atoms fixed upon a point in space, and yet modifying the laws that are around him by understanding them, and gaining, as it were, a kind of dominion over time and an empire in material space, and exerting on a scale infinitely small a power seeming a sort of shadow or reflection of a creative energy, and which entitles him to the distinction of being made in the image of God and animated by a spark of the Divine Mind. Whilst chemical pursuits exalt the understanding, they do not depress the imagination or weaken genuine feeling; whilst they give the mind habits of accuracy by obliging it to attend to facts, they likewise extend its analogies, and though conversant with the minute forms of things, they have for their ultimate end the great and magnificent objects of Nature. They regard the formation of a crystal, the structure of a pebble, the nature of a clay or earth; and they apply to the causes of the diversity of our mountain chains, the appearances of the winds, thunderstorms, meteors, the earthquake, the volcano, and all those phenomena which offer the most striking images to the poet and the painter. They keep alive that inextinguishable thirst after knowledge which is one of the greatest characteristics of our nature, for every discovery opens a new field for investigation of facts, shows us the imperfection of our theories. It has justly been said that the greater the circle of light, the greater the boundary of darkness by which it is surrounded. This strictly applies to chemical inquiries, and hence they are wonderfully suited to the progressive nature of the human intellect, which by its increasing efforts to acquire a higher kind of wisdom, and a state in which truth is fully and brightly revealed, seems, as it were, to demonstrate its birthright to immortality.

Eub.—I am glad that our opposition has led you to so complete a vindication of your favourite science. I want no further proof of its utility. I regret that I have not before made it a particular object of study.

Phil.—As our friend has so fully convinced us of the importance of chemistry, I hope he will descend to some particulars as to its real nature, its objects, its instruments. I would willingly have a definition of chemistry and some idea of the qualifications necessary to become a chemist, and of the apparatus essential for understanding what has been already done in the science, and for pursuing new inquiries.

The Unknown.—There is nothing more difficult than a good definition, for it is scarcely possible to express in a few words the abstracted view of an infinite variety of facts. Dr. Black has defined chemistry to be that science which treats of the changes produced in bodies by motions of their ultimate particles or atoms, but this definition is hypothetical, for the ultimate particles or atoms are mere creations of the imagination. I will give you a definition, which will have the merit of novelty and which is probably general in its application. Chemistry relates to those operations by which the intimate nature of bodies is changed, or by which they acquire new properties. This definition will not only apply to the effects of mixture, but to the phenomena of electricity, and, in short, to all the changes which do not merely depend upon the motion or division of masses of matter. However difficult it may have been to have given you a definition of chemistry, it is still more difficult to give you a detail of all the qualities necessary for a chemical philosopher. I will not name as many as Athenæus has named for a cook, who, he says, ought to be a mathematician, a theoretical musician, a natural philosopher, a natural historian, &c., though you had a disposition just now to make chemistry merely subservient to the uses of the kitchen. But I will seriously mention some of the studies fundamental to the higher departments of this science; a man may be a good practical chemist perhaps without possessing them, but he never can become a great chemical philosopher. The person who wishes to understand the higher departments of chemistry, or to pursue them in their most interesting relations to the economy of Nature, ought to be well-grounded in elementary mathematics; he will oftener have to refer to arithmetic than algebra, and to algebra than to geometry. But all these sciences lend their aid to chemistry; arithmetic, in determining the proportions of analytical results and the relative weights of the elements of bodies; algebra, in ascertaining the laws of the pressure of elastic fluids, the force of vapour as dependent upon temperature, and the effects of masses and surfaces on the communication and radiation of heat; the applications of geometry are principally limited to the determination of the crystalline forms of bodies, which constitute the most important type of their nature, and often offer useful hints for analytical researches respecting their composition. The first principles of natural philosophy or general physics ought not to be entirely unknown to the chemist. As the most active agents are fluids, elastic fluids, heat, light, and electricity, he ought to have a general knowledge of mechanics, hydrodynamics, pneumatics, optics, and electricity. Latin and Greek among the dead and French among the modern languages are necessary, and, as the most important after French, German and Italian. In natural history and in literature what belongs to a liberal education, such as that of our universities, is all that is required; indeed, a young man who has performed the ordinary course of college studies which are supposed fitted for common life and for refined society, has all the preliminary knowledge necessary to commence the study of chemistry. The apparatus essential to the modern chemical philosopher is much less bulky and expensive than that used by the ancients. An air pump, an electrical machine, a voltaic battery (all of which may be upon a small scale), a blow-pipe apparatus, a bellows and forge, a mercurial and water-gas apparatus, cups and basins of platinum and glass, and the common reagents of chemistry, are what are required. All the implements absolutely necessary may be carried in a small trunk, and some of the best and most refined researches of modern chemists have been made by means of an apparatus which might with ease be contained in a small travelling carriage, and the expense of which is only a few pounds. The facility with which chemical inquiries are carried on, and the simplicity of the apparatus, offer additional reasons, to those I have already given, for the pursuit of this science. It is not injurious to the health; the modern chemist is not like the ancient one, who passed the greater part of his time exposed to the heat and smoke of a furnace and the unwholesome vapours of acids and alkalies and other menstrua, of which, for a single experiment, he consumed several pounds. His processes may be carried on in the drawing-room, and some of them are no less beautiful in appearance than satisfactory in their results. It was said, by an author belonging to the last century, of alchemy, “that its beginning was deceit, its progress labour, and its end beggary.” It may be said of modern chemistry, that its beginning is pleasure, its progress knowledge, and its objects truth and utility. I have spoken of the scientific attainments necessary for the chemical philosopher; I will say a few words of the intellectual qualities necessary for discovery or for the advancement of the science. Amongst them patience, industry, and neatness in manipulation, and accuracy and minuteness in observing and registering the phenomena which occur, are essential. A steady hand and a quick eye are most useful auxiliaries; but there have been very few great chemists who have preserved these advantages through life; for the business of the laboratory is often a service of danger, and the elements, like the refractory spirits of romance, though the obedient slave of the magician, yet sometimes escape the influence of his talisman and endanger his person. Both the hands and eyes of others, however, may be sometimes advantageously made use of. By often repeating a process or an observation, the errors connected with hasty operations or imperfect views are annihilated; and, provided the assistant has no preconceived notions of his own, and is ignorant of the object of his employer in making the experiment, his simple and bare detail of facts will often be the best foundation for an opinion. With respect to the higher qualities of intellect necessary for understanding and developing the general laws of the science, the same talents I believe are required as for making advancement in every other department of human knowledge; I need not be very minute. The imagination must be active and brilliant in seeking analogies; yet entirely under the influence of the judgment in applying them. The memory must be extensive and profound; rather, however, calling up general views of things than minute trains of thought. The mind must not be, like an encyclopedia, a burthen of knowledge, but rather a critical dictionary which abounds in generalities, and points out where more minute information may be obtained. In detailing the results of experiments and in giving them to the world, the chemical philosopher should adopt the simplest style and manner; he will avoid all ornaments as something injurious to his subject, and should bear in mind the saying of the first king of Great Britain respecting a sermon which was excellent in doctrine but overcharged with poetical allusions and figurative language, “that the tropes and metaphors of the speaker were like the brilliant wild flowers in a field of corn—very pretty, but which did very much hurt the corn.” In announcing even the greatest and most important discoveries, the true philosopher will communicate his details with modesty and reserve; he will rather be a useful servant of the public, bringing forth a light from under his cloak when it is needed in darkness, than a charlatan exhibiting fireworks and having a trumpeter to announce their magnificence. I see you are smiling, and think what I am saying in bad taste; yet, notwithstanding, I will provoke your smiles still further by saying a word or two on his other moral qualities. That he should be humble-minded, you will readily allow, and a diligent searcher after truth, and neither diverted from this great object by the love of transient glory or temporary popularity, looking rather to the opinion of ages than to that of a day, and seeking to be remembered and named rather in the epochas of historians than in the columns of newspaper writers or journalists. He should resemble the modern geometricians in the greatness of his views and the profoundness of his researches, and the ancient alchemists in industry and piety. I do not mean that he should affix written prayers and inscriptions of recommendations of his processes to Providence, as was the custom of Peter Wolfe, and who was alive in my early days, but his mind should always be awake to devotional feeling, and in contemplating the variety and the beauty of the external world, and developing its scientific wonders, he will always refer to that infinite wisdom through whose beneficence he is permitted to enjoy knowledge; and, in becoming wiser, he will become better, he will rise at once in the scale of intellectual and moral existence, his increased sagacity will be subservient to a more exalted faith, and in proportion as the veil becomes thinner through which he sees the causes of things he will admire more the brightness of the divine light by which they are rendered visible.