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motives or of the effects of their acts on civili- His election gave general satisfaction to the zation.

Republicans. He took his seat March 4, 1879. CARPENTER, Matthew H., born in More- Among several speeches which he addressed to town, Vermont, in 1824; died in Washington, the Senate, all remarkable for their ability, that February 24, 1881. In 1843 he entered the against the Fitz John Porter bill is regarded as Military Academy at West Point, where he re- his finest effort. His course in politics during mained two years. He then went to Boston his last term in office was much more indeand studied law with Rufus Choate, and was pendent than previously, and as a lawyer he admitted to the bar. In 1848 he removed to bad few equals in Washington, where most of Wisconsin, and entered the practice of his pro- bis later years were spent. fession, in which he soon became eminent for CENSUS OF THE UNITED STATES. his legal ability and brilliant talent, which won (See UNITED STATES Census.) him high reputation in the Supreme Court of CHEMISTRY. The president of the Chemthe United States even before his entrance into ical Section of the British Association, Professor public life. Not until after the war did Mr. A.W.Williamson, made the growth of the atomic Carpenter take an active part in politics. Be- theory during the last fifty years the subject of fore and during the war he was a Democrat; his opening address at the last year's meeting, but, when the leading men took sides on that maintaining that its general validity had been issue, he became a Union man. When, at the confirmed by the tests of experimental applicaclose of the contest, he espoused Republican- tion to which it bad been rigorously subjected. ism, his generally recognized ability cominand- The binary or dualistic theory of combination, ed for him the active support of that party in and the doctrine of multiple proportions which Wisconsin, and in 1869 he was elected to the were formerly connected with it, and which United States Senate in place of Senator Doo- seemed to be satisfactorily applicable to the little.

simpler compounds and the salts, broke down Mr. Carpenter served in the Senate from when chemists came to deal with double comMay 4, 1869, until March 3, 1875, and occa- pounds which were not saline in character, and sionally showed great power as a lawyer and with the carbon compounds; and it became debater, but lacked those qualities necessary to necessary to find other methods of accounting make a public man understand public senti- for the phenomena of chemical combinations. ment. He belonged to that class of brilliant As the investigations were continued with refpoliticians who so strongly influenced the pro- erence to this object, the idea of substitution ceedings of Congress from 1869 to 1875, and came to be more and more used in the place of of which General Butler was a representative that of mere additive combination. Elementman. About this time Mr. Carpenter was the ary chemical reactions which, according to the victim of malicious slanders, but he was able to binary theory, were supposed to consist of prove to general satisfaction that they were dualistic processes, involving sometimes the groundless. In 1874 Wisconsin Republicans, assumption of forces (like predisposing affinity) like the party elsewhere, were suffering from of a purely metaphysical character, were exthe injudicious action of Congress upon the plained as consisting of atomic displacements, salary bill and like matters, and the feeling or interchanges of a kind well known to be of against the railroad corporations was also a common occurrence. Many products of the distracting element. The party had, however, combination of known molecules have been a majority in the Legislature, but a considera- found to be formed by processos of double deble portion of it was made up of Independents. composition, so that each molecule of such Mr. Carpenter received the caucus nomination products is built up .partly of atoins derived for Senator, but the independent minority from one of the materials, partly of atoms refused to vote for him. After a protracted from the other. In the organic compounds, struggle, the Democrats joined the independent many of the molecules having a very complex Republicans and elected Mr. Cameron. Mr. structure have been found to undergo in their Carpenter accepted bis defeat, vouched for the reactions very simple changes, of the same Republicanism of his successor, and retired to kind as those which mineral compounds underhis extensive law practice, taking little interest go. Families of organic compounds have been in political affairs. During the contest over discovered whose members are connected by the presidential succession of 1876–77, Mr. close analogy of constitution and properties, Carpenter appeared before the Electoral Com- each of them forming a series, each term of mission as one of the Tilden counsel, and made which is a compound whose molecule contains an argument in his behalf. The Legislature of one atom of carbon and two atoms of hydrogen Wisconsin, which met in January, 1879, was more than the previous one. Our knowledge called upon to choose a successor to Senator of molecules has undergone a most remarkable Howe. The contest between Messrs. Howe, and important extension by the discovery that Keyes, and others was a bitter one, and finally various elements in wbat we are accustomed Mr. Carpenter was presented as a compromise to consider the free state, really consist of candidate. He had been approved on financial molecules containing like atoms combined with questions, and his superior talents rose para- one another. Those marvelous varieties of mount over all the opposition formerly urged. matter called isomeric compounds have found

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their natural explanation in differences of the re- iamson regards the opinion that atomic values spective arrangement of like atoms. The term are invariable, or are variable only within par“equivalent" was introduced to indicate the ticularly defined limits, as an error. proportional weights of analogous substances marked in a recent address that he had been which were found to be of equal value in frequently struck by the fact that two theotheir chemical effects. Tables of the equivalent ries

, believed at one time to be conflicting, had weights of acids were made, representing the been shown by the progress of study to be both proportions of the several substances that were true. Such was the case with the rival thefound to be of equal value in neutralizing a ories, one of which represented molecules as fixed quantity of a certain base; and similar constructed after the pattern of three or four tables were made for the bases, as well as for types, while the other viewed them as containthe elements themselves. But little attention ing complex groups called radicles. Opposiwas paid under the dualistic system to the es. tion existed at one time between those who sential difference between atomic weights and made use of atomic weights and those who equivalent weights; but under the later devel- employed equivalent weights; and the most opments of the theory of the functions of important step that has of late been taken is atoms, it has become necessary to study the the introduction of the notion of equivalence relation of equivalence between elementary into the atomic theory. An inspection of the atoms, instead of studying them from the point series of hydrogen compounds with chlorine, of view of elements divisible in any proportion. oxygen, nitrogen, and carbon, will show that From this has sprung the division of the ele- the atom of chlorine, which combines with a ments into classes consisting respectively of single atom of hydrogen, has a different value equivalent atoms known as monads, dyads, from the atoms of oxygen, nitrogen, and carbon, triads, tetrads, etc., the character of which is which combine respectively with two, three, well represented in the four typical compounds, and four atoms of hydrogen. Hence, nitrogen Cl H, OH, NH3, CH4, where chlorine ap- and other elements of like equivalence are called pears as a monad, oxygen as a dyad, nitrogen trivalent or triads, while other elements are as a triad, and carbon as a tetrad. This has classed, according to the exponents of their probably been one of the most important steps equivalence in groups, as monads, dyads, penyet made in the development of the atomic tads, etc. Kekulé still holds that an element can theory, and has been seen to correspond in so belong to only one of these groups; that nitroclear and striking a manner with a vast number gen, for instance, is trivalent only, and that in of well-known properties and reactions of com- sal-ammoniac, where it is combined with five pounds as to deserve and acquire the confident other atoms, instead of being pentivalent, it is trust of chemists. Another great step has re a molecular compound of two chemical comcently been made which may be destined to pounds-ammonia and hydric chloride; and lead to most important results. It has been that the atoms of constituent molecules and discovered that if we arrange the elements in the molecules themselves were held together the empirical order of their respective atomic by different forces, one being molecular, the weights, beginning with hydrogen, and pro- other che cal. We have, however, no grounds ceeding thence step by step up to the heaviest for assuming a difference between chemical atom, we shall have before us a natural series and physical forces, and Kekulé's theory is no with periodically recurrent changes in the longer tenable. The theory commonly in vogue chemical and physical functions of its mem is that atoms vary in value within certain narbers. Of course the series is still imperfect, row limits; that nitrogen, for instance, is either and exhibits gaps and irregularities; but some trivalent or pentivalent. Professor Williamof the gaps have been filled up by the discov son recognizes no limitation to atomic value; ery of elements possessing the anticipated but le knows that many elements have atomic properties, inducing the hope that the others values greater than those commonly assumed. may be filled. The generalization affords a The character of the atoms often materially brilliant addition to the previous corrobora- affects the result. Thus gold can not combine tions of the reality of the units of matter with more than three atoms of chlorine alone, which chemists have discovered. But little but it can take up an additional atom of chloaccount has as yet been taken of atomic mo- rine if supplied with an atom of sodium. In tions; but it has been proved that the heat of this way we get the common double chloride combination affords a measure of its force, and of gold and sodium, NaAuCla, in which the we know that, in giving off heat, particles of gold is pentivalent. We are not to consider matter undergo a diminution of the velocity of the sodium as being here combined with the their motion. The force of chemical combina- gold as such, but as combined with the whole tion is evidently a function of atomic motion, group. Temperature, also, has an influence but a vast amount of work will be required to upon the atomic value of elements, a rise of develop the atomic theory to the point of ex- temperature tending to diminish it. plaining the force of chemical action in precise Molecular Weight of Hydrofluoric Acid.terms of such motion.

Professor J. W. Mallet has made some studies ATOMIC AND MOLECULAR WEIGHTS. - Varia- of the atomic weight of hydrofluoric acid, tions in Atomic Value.-Professor A. W. Will- with a view to finding an explanation of some

peculiar differences in the behavior of fluo- ceived atomic weight, 198•ő, being above that rine in entering into combination with other of gold, while the theory requires that it should elements. The analogies of fuorine with the be below that of iridium. halogens on the one hand, and with oxygen Molecular Weights of Decipium and Samaon the other hand, have often been remarked rium.-M. Delafontaine, in 1878, described an upon. The compounds of fluorine generally earth having a molecular weight of about 122, bear resemblance to compounds of chlorine, which he had obtained from samarskite, and but some striking differences in the character which he called decipia, regarding it as an oxide of these compounds have also forced themselves of a new metal, decipium. He has continued his upon the attention ; and the tendency of the studies of this substance, and has been brought fluorides to the formation of double salts, with to regard it as a mixture of two oxides, one of formulas analogous to those of oxygen com- them having a molecular weight of about 130, pounds, and the formation of salts including and the other a lower molecular weight. The both oxygen and fluorine, has suggested that former substance gives no absorption spectrum, some close natural relation may exist between while the second gives the spectrum which these elements themselves. There has, there. M. Delafontaine described in 1878 as that of fore, been ground for questioning whether fluo- decipia. M. Lecoq has also announced the rine should be classed with chlorine among the discovery of a new metal in samarskite, cormonad elements, with the formula HF to rep. responding with the second substance detected resent hydrofluoric acid, and assigned an atom- by M. Delafontaine, to which the latter proic weight of 19, or with oxygen among the poses to give the name of samarium. The modyarls, with the formula H.F for hydrofluoric lecular weight of its oxide is believed to be less acid, and an atomic weight of 38. Professor than 117. Samaria appears to be identical Mallet's experiments bore a special reference to with the earth Y3, having a molecular weight this question. The result was such as to justify of 115, which M. Marignac has found in samthe assumption that at the temperature of 30° arskite, while that chemist's Ya, having a mocentigrade the molecule of hydrofluoric-acid lecular weight of 120.5, may be supposed to be vapor should be represented, not as HF, but a mixture of decipia and terbia. as H,F2, while at higher temperatures disso Atomic Weight of Aluminum.-Professor J. ciation takes place, leading to the production W. Mallet, considering that the estimation of of diatomic molecules of HF. The structure the atomic weight of aluminum was resting on of the molecule of double weight, H.Fa, may be an insufficient basis of accurate experiment, regarded as resulting from fluorine behaving has pursued, during three years, a course of not only as a monad, but also as a triad, and experiments for the revision of the determinaacting in double atoms like those of nitrogen tion, in which he has kept in view the princiin the di-azotic compounds. In such a condi- ples-1. That each process used should be as tion the element presents a pseudo-dyad char- simple as possible, and should involve as little acter, and becomes capable of replacing oxy as possible of known liability to error; 2. That gen and of manifesting the linking function of different and independent processes should be that element. This assumption, supported by resorted to as the means of checking each the experimental evidence brought forward by other's results; 3. That each process should Professor Mallet, may serve conveniently to ex- be carried out with quantities of material difplain the composition of a number of fluorine fering considerably from each other in succescompounds, whose formulas are difficult to sive experiments; 4. That only such other write in a satisfactory way if fluorine be con- atomic weights should be involved as may be sidered exclusively monad.

counted, among those already known, with the Atomic Weight of Platinum.—The group of nearest approach to accuracy. Three series of metals embracing osmium, iridium, and plati- experiments were conducted, of which the num has until recently exhibited a series of first series was based on the purification of amirregularities in that their atomic weights did monium alum; the second on the preparation not manifest hose relations to each other and purification of aluminum bromide; and the which their properties, in connection with third on the preparation and application of Meyer and Mendelejeff's theory of classification, pure metallic aluminum. The mean result of indicated they should bear. Dr. K. Seubert, the twenty-five experiments which were retwo years ago, undertook the revision of the garded as the more accurate of the thirty that atomic weight of iridium, and fixed it at 192 - were made, gives the atomic weight of alumi644, patting it below that of platinuin. He num as 27.02. This is believed by Professor has since fixed the atomic weight of platinum Mallet to bear in favor of Prout's law, which at 194:177, giving it the place above that of assumes that all the atomic weights are multiiridium and below that of gold, which the ples of that of hydrogen. theory requires it should occupy, while the Atomic Weight of Cadmium.-Mr. Oliver previous estimation of its atomic weight made W. Huntington, under the direction of Professit above that of gold. The ascending series, or J. P. Cooke, of Harvard College, has made iridium, platinuni, gold, is now, as to those a revisionary determination of the atomio three metals, agreeable to theory'; but osmium weight of cadmium. He used a pure bromide still occupies an anomalous position, its re- of cadmium, specially prepared for the pur

pose, and the bromide of silver, likewise spe- but is dissolved by ether. The nature of the cially prepared, for comparison. The mean of hydrocarbon oil may be determined after it a series of eight experiments gave 112.31 as the has been isolated, by observing its density, atomic weight of the metal. This determina- taste, smell, behavior with acids, and other tion is regarded as bearing against the validity qualities. of the hypothesis of Prout, that all atomic Professor G. Lunge, of Zürich, has perfected weights are multiples of that of hydrogen. and described a simple and inexpensive process

NEW PROCESSES. -Mr. Alfred H. Allen has in- for procuring pure naphthalen that will not dicated some valuable simple tests for the pres- discolor. Presuming that the discoloration of ence of hydrocarbon oils as adulterations in naphthalen is analogous to that of phenol, he animal and vegetable oils. The inethods for sought to remove the agent which caused it by the detection of these oils are based on the oxidation. For this purpose he added an oxidensity of the sample, the lower flashing and dizing agent in the ordinary chemical washing boiling points, the fluorescent character of the .of naphthalen, using manganese dioxide, with oils produced from petroleum, bituminous complete success. Other oxidizing agents might shale, and rosin, and the incomplete saponifi- be substituted for manganese dioxide, but a cation of the oil by alkalies. The taste of the cheaper one can bardly be obtained. Naphthaoil and its odor on being heated are also use- len prepared by this process has kept its pure ful indications. If undoubtedly fluorescent, an white color much longer than the “chemically oil certainly contains a mixture of some hydro- pore" naphthalen made by the secret process carbon, but the converse is not strictly true, as of the manufacturers. the Auorescence of some varieties of mineral A patent bas been taken out by M. Closson, oil can be destroyed by chemical treatment, of Paris, for a cheap and expeditious method and in other cases fluorescence is wanting. of obtaining magnesia from magnesium chloThe greater number of hydrocarbon oils em- ride. The crude lye of magnesium chloride is ployed for lubricating purposes are, however, treated with burned dolomite, or magnesian strongly fluorescent, and the remainder usually limestone, when the chlorine of the lye combecome so on treatment with an equal measure bines with the lime of the dolomite, so that if of strong sulphuric acid. If strougly marked, the latter is pure a magnesia of from 98 to 993 the fluorescence of a hydrocarbon oil may be per cent standard can be easily made on a large observed in presence of a very large proportion scale. The magnesia bricks prepared by this of fixed oil, but, if any doubt exist, the hydro- process at Leopoldshall resist even the flame of carbon oil may be isolated. The fluorescence the oxyhydrogen-blast. The cost is fifteen may be seen by holding a test-tube filled with shillings à ton. Sulphate of lime is obtained the oil in a vertical position in front of a win as a by-product of the process through the use dow, when a bluish bloom” will be perceived of calcium chloride to remove the magnesium on looking at the sides of the tube from above. sulphate that is present in the magnesium chloA glass rod dipped in the oil and laid on a ride, and is used by paper-makers under the table in front of the window so that the oily end name of pearl-hardening. The value of the shall be projected in the view against the dark new process in its bearing on the manufacture background of the floor, or a piece of black of fire-proof furnace-linings, crucibles, etc., is marble or smoked glass rubbed with a streak very great. of oil and held horizontally before a window, Herr A. Wagner recommends the following will make a very slight fluorescence, readily process, whichi bas proved very satisfactory perceptible. Turbid oil should be filtered, to for the limestone waters of Munich, for the get out the minute particles that might, by determination of the organic matter in water. reflection, give an appearance of fluorescence. After the determination of all the other conDilution with ether, to which a little mineral stituents of the water, he evaporates suitable oil imparts a strong blue fluorescence, gives an quantities to dryness and separates the dry excellent test. The hydrocarbon oil may be residue by means of distilled water into an driven off by heating it if its boiling-point is insoluble and a soluble portion, the latter of comparatively low, but may be better removed which contains the chief bulk of the organic and the quantity of it measured by saponifying bodies. In the insoluble portion, which in the it, and washing the solution of the soap with waters he has to deal with consists almost enether. The hydrocarbon may, in this case, be tirely of calcium and magnesium carbonates, recovered pure by separating the ethereal layer he determines the organic matter by igniting and evaporating it at or below a steam-heat. a dried specimen in a platinum crucible and A good alkaline preparation for this purpose treating subsequently with ammonium carboncan be made by dissolving caustic potash in ate in the customary manner. The portion methylated spirit. The washing with ether soluble in water, if nitrates are absent or are should be repeated several times. The ether- present only in a quantity too small to be deprocess is, however, not applicable to sperma- termined, is dried after evaporation in a platceti and the waxes, on account of the large inom capsule, weighed, heated to a very low quantities—so small in the other fats that it redness, and weighed again. If nitrates are need not be taken into account-of matter they present in larger quantities, so that the existcontain that is not acted upon by the alkaliesing organic matter would not suffice to con

vert the nitrates into carbonates, he adds to the arsenic as arsenious acid, is formed. This the soluble portion, after drying and weighing, is extracted with water till it has been made a little pure solution of sugar, evaporates to to give up its arsenic, and the reddish-brown dryness, and heats the platinum capsule gradu- fluid containing some organic matter is evapally and by piecemeal with a very small gas- orated to dryness. The residue is dissolved at flame, so that no deflagration may happen. a gentle heat with a definite quantity of dilute After prolonged but very gentle ignition, the sulphuric acid, and introduced to a Marsh's ap; sugar-charcoal is found burned away, when paratus for the decomposition of arseniuretted the residue is moistened with water containing hydrogen by artificial heat, to which a Buncarbonic acid, and weighed again after drying. sen wash-bottle and a device for graduating The loss of weight in this case expresses the the admission of the fluid have been added. weight of the organic substances and the dif- The resultant gas having been dried in a ference between the equivalent of the nitric chloride of calcium tube, is passed through a acid which was present and of the carbonic red-hot glass tube. Not a trace of arsenic acid which has taken its place. This difference passes by if the cooled tube is of proper can be easily calculated from the quantity of length. The apparatus is then filled with the nitrates as previously ascertained, and must hydrogen generated by the sulphuric acid-zino be deducted. This process is not absolutely process, and the glass tube, having been accurate, but Herr Wagner considers it more heated to redness, the arsenical solution in certain than others. Herr Wagner calls atten- concentrated form is mixed with sulphuric tion to the necessity, in experiments for deter- acid, and the mixture is slowly passed into a mining the solid residues, of protecting the separating funnel ; then more and stronger platinum or porcelain capsule in which the acid is added, and the heat is kept up till the water is treated against the accumulation of a decomposition is wholly effected. The arsenic deposit from the gas-flame, through which a being collected in the form of a mirror of liability to error in weight is incurred. For metal

, the tube is cut, at a safe distance from this purpose he uses a thin sheet of platinum, the mirror, and weighed. The arsenic is reinstead of the ordinary wire gauze, between moved by heating, and the tube is weighed the capsule and the flame.

again, when the difference gives the amount of Mr. Thomas Moore has published the follow- metallic arsenic. The method is capable of ing new process for the separation of nickel detecting as little as the one thousandth of a and cobalt from iron: Having removed any milligramme of the metal. In organic matters excess of free acid by evaporation, and dis- the experimenters have detected a millionth of solving the residue in water, add to the solu- a gramme in urine and in an extract from beef. tion a sufficient quantity of ammonic sulphate The experiments are claimed to show that the to form a double sulphate with the nickel and presence of organic matter in considerable cobalt present. Dilute to about 150 c. c., and quantity does not interfere with the recovery add a rather large excess of oxalic acid, and of the entire amount of arsenic. stir well. In case a precipitate form, more VEGETABLE ANALYSIS.-- Professor Henry B. ammonic sulphate should be added until a Parsons, of Washington, D. O., has described clear solution is obtained. Add ammonic hy- a method for the more accurate analysis of droxide in considerable excess; stir, heat plants. His apparatus includes a worm of gently for a few minutes, and filter;' wash block-tin pipe, suitably connected with a glass well with water containing ammonia; or di- percolator, within which is suspended a smaller lute to about 500 c. C., and, after allowing the tube, having a bottom of filtering-paper and precipitate to settle, withdraw a given portion fine, washed linen. The weighed sample of the of the clear upper stratum of liquid. This, finely-powdered herb is placed within this tube after a further addition of ammonic sulphate, for extraction. The solvent is introduced in a to lessen the resistance to the electric current, glass flask, tightly fitted to the outer percolator, is ready for electrolysis or any other method and is volatilized by the application of heat of estimating the nickel or cobalt.

through a water-bath.

A tared filter, preMessrs. R. H. Chittenden and H. H. Donald- pared by allowing fine asbestus, held in water, son, of the Sheffield Laboratory, Yale College, to settle on the perforated bottom of a platidescribe a process for the detection and de- num crucible, is also provided and connected termination of arsenic in organic bodies, which with the receiving-vessel, while this in turn is they recommend as very accurate, delicate, and connected with a Bupsen's pump. The air-dried simple. It is based upon Gauthier's process, specimen of the plant to be analyzed should be and somewhat resembles it, but requires for ground or beaten till all the particles will pass reagents only nitric acid, sulphuric acid, and through a sieve having from forty to sixty zinc. The organic matter is destroyed by meshes to the linear inch. A part of this successive oxidations with nitric and sulphuric should be further pulverized till it will pass acids, as in Gauthier's method, but at a much through a sieve having from eighty to one lower temperature. The suspected matter is hundred meshes to the linear inch. The finer then treated for fifteen minutes at 200° C., and part of the sample is employed in the immediate allowed to cool, when a hard, carbonaceous analysis, while the coarser part is reserved for residue, free from nitric acid, and containing the separation of those proximate principles

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