have been lost, that they have mouldered pear, as we say, before the public, and take among rubbish with an external appearance a more active part in passing affairs. It as unattractive as the materials with which does seem fitting that men who make disthey were surrounded, has often encouraged coveries should speak out plainly, and it is us to foster the weakest talents, and the a fine sight to see the influence such a voice meanest minds, whilst we have, consequent- has from the regions of pure science down ly, been compelled to suffer, for a time, the to the practical daily life of practical men. evils of a quackery which we ourselves have It is right that they who think and work carefully nourished. Too true it is, that should associate with others who think and from neglect, secret suffering has wasted work also, and whilst advancing knowledge many a soul capable of great exertions; and co-operate with them in furthering the gemen worthy of the highest estimation of neral progress of civilization. It may be said their fellow men have sunk from the exhaus- again, that such a state of things necessarily tion of repressed vigor; but, as Solon said, prevents deep learning; such certainly is a man cannot be accounted happy before he one of its evils; but if England is not so far dies, so may we say of the great. Fre- forward in certain departments as Germany, quently not seen, because the gift of speech, her learning has never fallen below the that speech which makes and commands an wants of the age, and the equability with audience, was not given them; because the which she has advanced, mentally and mainner life, that life in which the true great-terially, has more than compensated for the ness really consisted, was not combined with the executive power necessary to its effectiveness. Greatness is a movement forward which can be seen only by such as look forward with it, the exertion of a force which the enervated cannot sympathize with. England has been much blamed for want of affection towards its great men; the poverty of many, and the few salaries given by government to men of science and learning, having been looked upon as a proof. Surely the great thinkers of this country are not less known to it than the great thinkers of other countries are known to their fellows. We should rather say, that not even in those parts of the continent where education, to a certain extent is compulsory, is there to be found such a sympathy for a rising citizen as is seen in the British public. It is not by the executive part of the government that we must judge, not by any law to be found in parliamentary records, but by the general feeling of the people towards one who seems to show much of the great or the good. We all know that English individuality has never ceased to have a great influence in the progress of the nation, that the head only has not been at work, but every member, being full of life, has proved the energy of the system, and the healthy state of its sympathies. A bureau of learning may do much good, but it may also do evil by monopolizing the field; and at all events that system is bad which carries as sistance so far as to smooth down the difficulties which engender the most determined enthusiasm. The result of this system, or want of system, has been, that men mix themselves more with their fellow-men, ap prophetic strides taken by her relations. Such a system is no doubt more calculated to produce effective than truly great men; the first grow from the system, the second independently, and it requires a mind of unusual strength to resist the current that drags him onward in its course, and thereby to maintain a dignified individuality by following his own. On the other hand the secluded great, whilst he labors most and leaves greater results, fails to exercise that personal influence on those around him, one of the most important marks of genius, and he leaves to others his accumulated treasures, but no posterity to succeed to the inheritance of his power. Such is not the case with him who breathes so much of his own breath of life into his pupils or his friends, that men equal, and sometimes superior, are brought into life. But, as has been said, to unite the two at a time when science is gained with such labor, and popularity by so much time, is scarcely possible, without the evidences of at least a partial weakness. The works before us are the results of the labor of a man working out his own preconceived notions without regard to the events passing around him, a man long known to the scientific world as the father of chemistry, little known personally to scientific men, and not till late in life recognized by government as one who had done a great national service. He was born at Eaglesfield, near Cockermouth, Cumberland, Sept. 5th, 1766. Here the name of Dalton is familiar; the remarkable fact that every little spot there, but especially in Lancashire, is inhabited by persons bearing the same name as the place, shows much of candles. It is strange that this man, so dethe character and habits of the people, and servedly held on high, should all his life if they are furnishing now many names in have given so much praise to what he calls literature and in science, it may be because unwearied assiduity, that he should have this almost indigenous people have their almost despised the claims of genius, and race yet to run. The father of Dalton had looked to mere accumulation as the source a small estate, which seems to have been ajof power. No one can deny the power of considerable time in the family, and it be- riches, physical or mental, but fewer still came the property of John Dalton, after the the advantages of the mind fitted to use death of his elder brother, Jonathan, who them. Now it is remarkable that Dalton's inherited it from the father. In such a great work was done at a time when his place as Eaglesfield, and at such a time, we knowledge of chemistry was small, when he cannot suppose that a man could have had had almost no stores from which to draw; an opportunity of giving his son a good ed- and when in after years he had accumu ucation, and accordingly we find that he left lated an immense number of facts, the result school when about twelve years of age, and of his "unwearied assiduity," they in no soon after commenced a school of his own, wise added to his philosophy; but, let it be continuing it for two winters. In summer added, are a distinct proof that by listening he worked on the farm, helping his father. to the calls of his own genius, and by workIt may appear strange to many that a boy ing less, he would have accomplished more. of thirteen should keep a school, but such The atomic theory was formed complete, he has often occurred in the north of England did his part; the details which he in vain and in Scotland. An inquiring boy draws attempted to obtain with accuracy, were curious heads around him, and when once worked out by others, whilst his valuable put in motion their progress is not stopped time was lost in obstinately persisting to mauntil they leave their village imprisonment nipulate. for a greater scene of action and of thought; A cousin, of the name of George Bewley, and one, now an ornament to his profession kept a school at Kendal, in which Dalton's in London, learnt his grammar over his file brother Jonathan was usher. At the age of and vice during the day, and taught it to fifteen John Dalton joined him. Neither at others in the evening. We say this to put this time, nor at any other period of his life, in its true light the fact of Dalton's early does he seem to have attended to the literary teaching; it is the natural consequence of department of his studies, although he is an active mind among sluggish minds; the said to have learned Latin and Greek pretty rural population is not so highly educated, well, and to have had such an excellent that a boy of moderate education should not memory that he has brought to the recolbe able to take a much higher place in lection of students of ancient literature odes letters than they; and we see, by such ex- of Anacreon which he certainly had not amples, another instance of the power of read for forty years. A few old Greek knowledge on even mere mental activity, books were sold with his library, none of although in the possession of a mere child. which, however, seemed to have been openDalton's principal study was mathematics, ed frequently. But to have attended to which he learned in company with a boy of literature would have been an almost imthe name of William Alderson. This boy possible thing for John Dalton; his faculty was in the service of a gentleman of the of observation was great; his pleasure was place, who took notice of Dalton when he in observing and in notifying facts, and the was about ten years of age, and showed 200,000 meteorological observations are a him several marks of kindness. Diligence sufficient proof. He lived at Kendal eight seems to have been a distinguishing point in years; this portion of his life has less inDalton's character even at this early age, terest for us; it was chiefly a time of eduand he showed it often in encouraging the cation for him, and decided his future spirits of his companion, weary often with course. He became intimate there with a fruitless labor. Betting, which is on all gentleman of the name of Gough, a man points rather a favorite mode of settling who, although blind from infancy, was pos disputes there, being in reality a mere re-sessed of high scientific attainments. Physimove from the exercise of physical force, cal and mathematical science seem to have was resorted to also as an incentive to study, been his favorite pursuits, although, even and Dalton is said once to have gained, by as a botanist, he is said to have had high the solution of a problem, a winter's store of attainments; we find Dalton thanking him in his earlier works as an unknown friend, ( These observations were continued with and in his later works telling us his name, great care until the last day of his life, or and doing that justice to his character which rather the one preceding the morning of before his death Mr. Gough had forbidden his death; on this last day he is said to to be done. His occupation at this time, he have made a mistake in writing but aftersays, was to read and write for Mr. Gough, wards corrected it. In this space of time and to participate with him in the pleasure he made upwards of two hundred thousand of successful investigation. Mr. Gough was observations of various kinds relating to the first who kept a meteorological journal meteorology, and although the greater part at Kendal, and led Dalton into that branch are merely the noting down the state of of inquiry. the thermometer and barometer, this weary perpetuity of labor is more than most men can endure. No excitability made him pursue one subject when another ought to be attended to, no temptation led him out of his foredetermined course. At this time Dalton's name may also be found often in the 'Gentleman's and Lady's Diary,' in which he answered mathematical and philosophical questions. But we must not so soon leave Mr. Gough. Dalton, in his preface, has paid him the highest tribute of respect; has acknowledged that he received a great deal from him, and considers the germ of all his discoveries to be contained in that portion of his works which was written whilst studying along with Mr. Gough. When we look at such a man, we may well ask the question-By whom is civilization advanced? Is it by him who is known to the world, or by him who is unknown? The most difficult periods of a discovery, and the most dangerous, are the periods of birth and of growth. The first idea is dark and gloomy; it may be some mysterious-like feeling merely. The great man fosters it till it becomes clearer, till it takes a form; then it may be grappled with by a very ordinary man; but the last is looked on as the first, and the first is often unknown. Those who lived in that part of the country must have heard of Gough. Mr. Wordsworth has spoken of him in the 'Excursion' in the following words, to which allusion we are indebted to Mr. Crompton, of Manchester: "Methinks I see him, how his eyeballs roll'd From 1790 to 1793 Dalton was engaged in making observations, and in the latter year published his "Meteorological Observations and Essays." He then left Kendal and removed to Manchester. He is nowhere seen to more advantage than when, in the words of Prof. Sedgwick, he is bringing the turbulent elements themselves under his own intellectual domination. His observations on the weight of the atmosphere led him by degrees into chemical ground. He showed that every grain of water dissolved in air becomes an elastic vapor, capable of supporting 1-24th of an inch of mercury; that the rise of the barometer in summer indicated an increase in the amount of watery vapor in the air, and that the rise of the mercury did not depend on the specific gravity of the air only, otherwise summer and winter would show an equal barometer. He endeavored to connect the aurora borealis with magnetic phenomena, but found that this had been done before him by Dr. Halley. The same thing occurred with his explanation of the trade winds, which had been given long before by Geo. Hadley, F. R. S. Such mistakes occurred frequently, from the very little which he read; there are few branches of science which would allow of such proceedings at the present time, when observations are to be found so frequently in all departments, not certainly always of value but at least of some interest. In 1793 he went to Manchester, to be teacher of mathematics to the college there. In 1799, when the college removed to York, he separated from it, preferring to take private pupils, a practice which he kept up till late in life. It is a pity that he should have been so long employed in this manner, especially as he had no great talent for teaching, and his time would have been much better occupied in thinking and observing, but he is said to have preferred this when a more easily obtained competency was offered him, saying that teaching was an amusement, and that if richer, he would probably not spend any more time in study than he was then accustomed to do. About this time he wrote an English grammar, a book very little known, and its appearance seems anomalous, and difficult to account for, unless we suppose that circumstances of a pecuniary nature compelled him to study what he was certainly not naturally most inclined to. In this work the original thinker appears; a firm and independent character may be seen in it, although a mind like his is not best fitted for working with such changeable and volatile laws as those of grammatical inflection and construction. We shall merely take a short view of his writings and his career, attending chiefly to the character of mind displayed in them, and leaving more minute details to such as have documents relating to each particular event. His character of mind we have quoted from his writings as well as from his most intimate friends. In 1794, he became a member of the Literary and Philosophical Society of Manchester, when he read his first paper entitled "Facts relating to the Vision of Colors." He had that peculiarity of vision which cannot distinguish between red, pink, purple, and blue. He says, "I was never convinced of the peculiarity of my vision till I observed the color of the flower of the Geranium zonale by candle light, in 1792. The flower was pink, but it appeared to me an exact sky-blue by day; in candle-light, however, it was astonishingly changed, not having any blue in it, but what I called red, a color which forms a striking contrast to blue." He believed that this was to be attributed to the color of the fluids contained in the eye. It is true that there was found, on his death, a slight yellow color in the crystalline lens of the eye, but objects seen through it, when removed from the body, still preserved their natural color. be connected with an expression of excellence rather than of defect. The list of his papers and their dates are given in one of the works before us; those from 1793 to 1804 gradually conduct us from meteorology to chemistry. Having come from Kendal, a meteorologist and mathematician, he advanced with all the cognate branches of investigation. He endeavors to determine the relation between the quantity of rain and dew, and the amount of water removed by rains and evaporation, the origin of springs, the power of fluids to conduct heat, the heat and cold produced by mechanical condensation and expansion of the air, the constitution of mixed gases, &c. He comes from the consideration of air and vapor viewed as an atmosphere to the same bodies in a more purely chemical point of view. He has given the elasticity of vapor at different temperatures, shown the method of determining the amount of vapor in the atmosphere, and the rate of evaporation at different temperatures. He makes important observations on the more mechanical properties of gases. Amongst these is diffusion of gases, at least as far as the mechanical part is concerned. The action of gases towards themselves, he explains, is not the same as towards gases of a different nature. The particles of each gas possess a certain repulsion towards particles of the same kind, but the particles of two different gases do not possess this repulsion. This is the reason, that if two bottles of gases of a different kind be connected even by a very small aperture, they mix completely in a very short time. Even if the upper gas be the light hydrogen, and the lower carbonic acid, both will be found to be equally diffused through the upper and under bottle. He established also the law that all elastic fluids expand 1-480 every degree of heat from freezing point to 212°. His eyes being to himself an object of considerable speculation, his friends desired It will still be impossible to give in this that they should be examined on his de- place all his researches, and we must now cease. They were extracted by his friend attend to those parts which are more purely and medical attendant, Mr. Jos. Ransome, chemical, as his name has risen chiefly by and have since been examined by Sir Da-them, and he is best known in connection vid Brewster, without any further result than with them. It must, however, be rememthe opinion that the cause was functional, bered that the name of Dalton can stand not mechanical. Such a distortion of his high without the support of the atomic thecolor-sight could not fail to cause him someory; the investigations which have been annoyance at times, and tales of his strange mistakes in dress are told of him. It is a pity that any one should have given the name of Daltonism to this strange vision, for we must remember that, after all, few eyes were so good as Dalton's and ought to alluded to are a sufficient proof of this, and the improvements in meteorological observations, the great amount of data left by him, and the impulse given by him to the study, are works sufficient to point him out as one of the few, who, in submitting to the labor imposed upon humanity have had the pleasure of finding it worth more than the food and the raiment or any other necessary or pleasure which it procured for self alone. In considering the works of Dalton, the atomic theory must receive the chief attention; and to know the change which chemistry has undergone under it, we must first take a view of the chemistry of the period of the discovery, at least as far as it regards quantity, a word scarcely used in chemistry at the time, and an idea not defined but by the atomic theory. calculated the combining power of bodies, by numbers expressing force of attraction, a principle which could not have led to the first laws of the atomic theory with any certainty, but which would have been found entirely at fault when compound atoms came to be spoken of. If, however, his principles be insufficient, such cannot be said of his words, which do express the atomic theory, and even the doctrine of compound proportions which may be gathered from them. Dalton's friends confess the former, the knowledge of the atomic Wenzel observed the fact of the mutual theory, but claim for him that of multiple saturation of salts; when two salts mutually and compound proportions, lest he should decompose each other, a certain quantity, lose all the honor: but the truth is, that ex. gr. four of soda saturates an acid, whilst where the one is well known the other fourteen of lead is required, and five of sul- must follow with ease. Higgins says, phuric acid are required when six or seven" Let S be a particle of sulphur, D a parof nitric are necessary. Richter proceeded to analyze the different salts, and find the relative power of saturation of acids and bases, working on the fact known to Wenzel, the definite nature of the union which takes place between an acid and an alkali. He endeavored to establish accuracy in chemical calculations, but his view of the subject was too limited, his capacities of saturation were vague powers or forces, and wanted this unvarying unit which we shall see was introduced by Dalton, and gives the laws the form of a natural necessity. ticle of dephlogisticated air (or oxygen) attracted by a force of 6% and let the compound be volatile sulphuric acid. Let us suppose a second particle of dephlogisticated air to unite to S, so as to form perfect vitriolic acid; to receive the latter, S must relax its tendency for the former one half." In another part, again, he calls this a molecule of sulphuric acid, alluding to its union with bases. In another place (pages 36— 37 of the edition, London, 1791) he says, 100 grains of sulphur require 100 or 102 of the real gravitating matter of dephlogis Bergman had some very good notions on ticated air (oxygen) to form volatile vitriolthe relations of oxides and metals; he ic acid, and as volatile vitriolic acid is very weighed the precipitated oxide, and calcu- little short of double the specific gravity of lated its relation to the metal used, the mode dephlogisticated air, we may conclude that certainly of arriving at an atomic weight, the ultimate particles of sulphur and debut in him also the possible took place of phlogisticated air contain equal quantities the necessary and unchangeable. of solid matter; for dephlogisticated air sufOf all men who attended to this subject fers no considerable contraction by uniting before Dalton, who saw most clearly how to sulphur, in the proportion merely necesthe matter stood, was Higgins, of Dublin.sary for the formation of a volatile vitriolic It is remarkable that in some places he acid. Hence we may conclude that a sinhas reasoned according to the true princi-gle ultimate particle of sulphur is intimateples of combination, but not himself seeing ly united to a single ultimate particle of clearly the foundation of his reasoning, he dephlogisticated air, and that in perfect failed in coming to an universal expression vitriolic acid every single particle of sulfor the facts. Or if he did see his way he phur is united to two of dephlogisticated failed in seeing its value, its use in investi- air." Considering that it was impossible gation, its value in analysis, its many ap- at that time to see the true atomic weight plications in theory and in practice, and its of oxygen, we consider that Higgins had a grandeur and beauty as a law of nature. good right to say that sulphurous acid conHe showed that a body uniting with oxy-tained one atom of each; and that if such gen took up first one particle, then another, be the case, the atomic weights of sulphur and so on; that every particle united with and oxygen are equal. This is reasoning a certain force, whilst the first particle in the true spirit of the theory. Had he would have a greater force than the second measured more accurately, the addition in and the second than the third, calculating weight necessary to form sulphuric acid, the force of combination by numbers. he would have seen that it did not contain He |