remained a mystery. This phenomenon appears especially, but not exclusively, after a sudden death due either to wounds received upon the field of battle or elsewhere, or to other causes, but almost always when there has been an intense excitement, and o'ten also when great bodily fatigue has preceded the last moment of life. The principal feature of this curious fact is the persistence after death of the expression of the face or of certain attitudes of the limbs or body, or of both. Such persistence exhibits itself clearly in certain cases; for example, when, despite the sudden cessation of life, a limb that is raised does not drop, or when the body of a man standing, or seated upon horseback, does not fall over. In order to clearly understand the terms of the problem to be solved in reference to this phenomenon, it is absolutely necessary to know (1) that our attitudes and facial expression depend upon a contraction of our muscles due to an influence of the nervous centres, and (2) that such influence necessarily ceasing at the instant of death, a relaxation must also necessarily occur in all the muscles that were contracted, unless some other agency at once replaces that which has disappeared and causes the same physical state to persist that formerly existed therein. The question, then, is this: What is the agency that, as soon as the faculty of volition vanishes, takes the place of the latter, or at least produces in the muscles an organic state that prevents all relaxation? The object of this article is to auswer this question, and to show that the cause or agency to be discovered is not the sudden appearance of that state of muscular stiffness known by the name of rigor mortis or cadaveric rigidity, but that such agency is found in a peculiar action of the nervous centres that manifests itself a little before or at the instant of death. One of the most striking examples of the strange fact that I am about to study was observed by Dr. Rossbach, of Wurzbourg, upon the battlefield of Beaumont, near Sedan, in 1870. He found the corpse of a soldier half sitting, half reclining, upon the ground, and delicately holding a tin cup between his thumb and forefinger and directing it toward a mouth that was wanting. The poor man had, while in this position, been killed by a cannon ball that took off his head and all of his face except the lower jaw. The body and arms at the instant of death had suddenly taken on a rigidity that caused them to afterwards remain in the position that they were in when the head was removed. Twenty-four hours had elapsed since the battle, when Dr. Rossbach found the body in this state. remarkable: A detachment of United States post mortem rigidity) in all the limbs and all other In the first work of any importance in which this subject has been treated of, Dr. Chenu relates that a French military surgeon, Dr. Perrier, was greatly surprised upon going over the battlefield of Alma, the day succeeding the terrible couflict, to see that many corpses of Russian soldiers had attitudes aud expressions of countenance like those of living persons. Some of these corpses had the different expressions that characterise anguish, suffering, or despair. Others, on the contrary, had the appear-importance to life is the most frequent cause of the ance of greater calmness and resignation. One case, particularly, attracted the doctor's attention, where the body lay stretched out upon the ground, the knees bent, the hauds clasped and lifted in the air, and the head thrown back, as if death had come upon the individual while he was reciting a prayer. In addition, many other persons who have visited battlefields immediately after a conflict tell us that they observed numbers of corpses that were still holding their guns or sabres. Some seemed to be biting their cartridges, while others, still upon horseback, continued to preserve the attitude they had at the moment of death. These phenomena have been studied with special attention by Dr. Armand at Magenta, by Baron Larrey at Solferino, and by Dr. Baudin at lukermann. I owe to the kindness of Dr. S. Weir Mitchell a knowledge of an excellent memoir by Dr. John Brinton, of Philadelphia, upon the Rigidity which Accompanies Sudden or Violent Death a work in which the question under consideration is studied with the greatest care. Speaking of the field of battle of Antietam, Dr. Brinton says that he counted forty corpses over a space of from 40 to 50 yards square, and he gives us the following picture of what he observed in this place:-"Several of these corpses were lying in extraordinary attitudes, some with their arms uited aud rigid, and others with their legs drawn up toward the trunk, and stiff. With others, in quite large number, the trunk was curved forward and also rigid. In a word, these attitudes were not those of the state of relaxation produced by death, but rather those of an apparently active character, doubtless due to a final inuscular act at the very moment of the extinctions of life-a spasmodic act that had left the muscles stiff and inflexible. Death in the majority of these cases had been caused by wounds made in the breast aud, less frequently, by balls that had traversed the head or abdomen. In the latter cases there had been considerable hemorrhage, as was proved by the pools of blood of dark colour near the sides of the bodies. This inspection was made thirty-six hours after death, or still later." The following three cases related by Dr. Brinton (which were furnished to him by friends) are very Death, in man as in animals, takes place in two ways that differ radically from each other. On the one hand, it may supervene suddenly, either through the influence of excitement or that of a wound or blow, or, again, through the following causes:-The impression produced by submersion in cold water, or in almost icy water, and the impression produced sometimes, in persons who are eminently nervous, by the least lesion affecting certain parts of the body. In this kind of death there may not be even the least vital manifestation after the last sigh, except a feeble action of the heart that scon disappears. All the cerebral faculties give way suddenly-consciousness, intelligence, the will, the perceptive faculties, sensorial and sensitive impressions, and respiratory motions all disappear at once. There is no agony, and none of that struggle that usually precedes death. The body suddenly loses its temperature, and cadaveric rigidity comes late and lasts considerably. Dr. Henry Stille relates that, while seated upon a freight car on the Nashville and Chattanooga Railroad, he saw a brakeman instantly killed by a ball which struck him between the eyes, a mortal wound that was given by a guerilla who lay in ambush in a forest through which the train was passing. The man thus killed was tightening the brake when he received the ball. After his death his body remained fixed, the arms In the other kind of death, which is the one that extended and stiff on the handwheel of the brake. we usually observe, there is, on the contrary, a The pipe that he was smoking remained fastened genuine struggle in the still living organism, between his teeth. The rigidity was so perfect, especially when life is ending through the and his hands were so tightly closed, that it was effect of certain wounds or of a great scarcely possible to free the corpse and make it let hemorrhage, or as & consequence of a comgo its hold. A maintenance of the last attitude plete and sudden deprivation of respiration. may occur under circumstances other than a sudden The heart in such a case beats violently, death produced by lesions of the brain, heart, the efforts made to breathe are extremely or lungs, although an injury to an orgau of great energetic, consciousness and the cerebral faculties may keep up for a short space of time, and after phenomena. Dr. Brinton has observed it after this, great agitation or general convulsions occur. wounds made in the abdomen, and Dr. Armand, in The temperature of the body rises, and this increase a single case, through a wound of the thigh. Yet may still continue for some little time after the last this phenomenon does not manifest itself exclu-effort is made to breathe. Cadaveric rigidity sively in cases where death results from wounds. appears early, but never immediately. My experi It was observed in a horrible accident that hap-ments and the details of the cases that I have pened in London in 1867, when forty-one persors, related show that the persistence of the last skating upon Regent's Park Reservoir, perished through the sudden giving way of the ice. The following extract from the Times concerning this event is full of interest:-"The attitude of the majority of the persons who were taken from the water has given rise to numerous discussions in the medical journals. In almost all cases the arms were raised, and sometimes the elbows were pressed against the sides. In other cases the elbows formed a right angle, and projected as in the act of skating. It may be concluded that these unfortunates were resting upon the ice with their arms, not daring to use their hands, and that when, on becoming exhausted, they died, it was not through asphyxia, but rather through the action of cold and fright; and this would explain why they preserved the position in which they were found." Dr. Taylor had already mentioned the case of an individual who had for a long time held his arms extended to avoid being drowned, and in whom, after death, these limbs were found stiffened out in the same position. It seems that carbonic acid is cable of producing that special rigidity of the muscles that maintains the trunk and limbs in the attitude that the last act of the will has caused them to assume. In 1832 Dr. Von Graefe saw, in the grotto of Pyrmont, the corpse of a young man who had voluntarily put an end to his days by exposing himself to the carbonic ALLOYS USED FOR COINAGE.-II.* acid gas that fills this cavern. The body was found By Prof. W. CHANDLER ROBERTS, F.R.S., Chemist half seated upon the ground. One of the hands of the Royal Mint. supported the head, as if the young man had desired to avoid touching the wall, against which the upper guage, is different from that ordinarily acTHE meaning of the word alloy, in mint lanpart of his body rested. The trunk was bent toward the right. The attitude of the body had cepted in scientific phraseology, as it is applied to the appearance of a person asleep and reposing the base metal added to a more precious one, and peacefully. How shall we explain this curious not to the mass, which may be either molten or series of facts? We know that sooner or later • An abstract of the Cantor Lectures, delivered before there supervenes a stiffness (called cadaveric or the Society of Arts, attitude does not occur in all cases of death belonging to the first of the two types just described; but facts indicate that this singular phenomenon occurs only in cases of death that belong to this type. In one of the conclusions of Dr. Brinton's excellent memoir, he says that in the cases of persistence of attitude that have been observed upon the battlefield, and that he describes, death had probably been instantaneous, without being accompanied with convulsions or agony. It results from the facts that I have stated in this paper, and from the experiments, that I have done nothing more than allude to-(1) that the preservation after death of the attitudes of life, and of the facial expression, does not depend upon the sudden appearance of what is called cadaveric or post mortem rigidity, but upon the production of a vital act of rigidity or tonic contraction, like the fixed spasm that we often see in hysterical or paralytic persons; and (2) that a number of causes of death, acting without the ordinary agony, may produce that strange phenomenon which is characterised by a persistence after death of the attitude and facial expression that existed at the moment of the last sigh. as to solidified, of the mixed metals. This use of the the total difference between the molecular grouping lead. In a dissertation on the Homeric talent, Dr. word has been fostered by the way in which it has, of a pure metal and an alloy is afforded by their F. Haltsch states that it weighed 16.8 grammes, or from time to time, been employed in ordinances electrical behaviour. It will, I trust, be evident a little above oz. troy, and was the prototype of that have regulated the composition of the coin, that the base metal added to gold or silver may be the oldest gold stater, coined in the beginning of and in the indentures made between the Sovereign regarded from two distinct points of view; either the 7th century B.C., at Phocea, and other cities of and the Master of the Mint. It has also been as a useful constituent of the coin, which enables it Asia Minor. The numerous analyses made by perpetuated by the first schedule of the Coinage to resist wear and hinders the obliteration of its im- Dr. Rauch and others have placed at our Act, 1870, the legislative enactment which guides pression, or, if coins containing base metal are made disposal much accurate information the currency at the present time. The earliest of current at more than their intrinsic value, as a the standard fineness of the alloys used for these ordinances extant, that given by King Ed-source of gain to the rulers of the country. With coinage in Greek and Roman times. With ward I. to Gregorie Rokesley, prescribes that a regard to the actual standards of fineness which regard to Roman money, I will only quote pound of silver money shall contain "11 ounces, 2 have, from time to time, been employed, it may be Lenormant's statement, that the gold of the Repubeasterlings (dwts.), and 1 farthing of silver, and pointed out that, in the numismatic history of the lic was always pure, and that Imperial gold coins, the other 17 pence 3 farthings to be 'lay,' that is, world, endless combinations of precious and base until the time of Vespasian, were of excellent alloy.'" Throughout these lectures the words metal have been represented. Pure gold and silver quality, although their standard was slightly "standard fineness" indicate the amount of have been used, either singly, or alloyed with each reduced, that is, from pure gold to standard 991. "fine" or pure metal present in any given alloy, other, or alloyed with copper, the latter metal, in After the time of this emperor, the standard and the degree of fineness will be expressed deci- turn, being sometimes employed with only infini- appears to have fallen to 938, and subsequently, mally, pure gold or pure silver being considered to tesimal additions of precious metal. The alloys about the time of Septimius Severus, it fell much be 1,000. The reasons for the use of alloys, in actually used for coinage at the present time are lower. In the year 265 A.D. the gold coins were preference to pure metals, are somewhat complex. not numerous, and it may be well to begin the struck in a base alloy, containing: 827-3 of copper, In early states of civilisation coins are generally consideration of such as are specially important by 159-4 of silver, 133 of gold; total, 1000-0. The made of more or less pure metal, but a nation does tracing the steps which led to their adoption. In silver of the Republic was always excellent, varynot advance far in its history before the very im- the case of both the gold and silver currency of this ing, according to Darcet, from 993 to 995, but portant fact is recognised that alloys are more country, the adjustment of the relative proportions under Imperial rule its debasement appears to have durable than pure metals, and that their substitu- of the precious and the base metals was undoubtedly been rapidly effected, especially from the time of tion for pure gold or silver affords a notable source guided by the particular systems of weights used. Nero until the third century, when the silver of revenue. In cases where the coinage is in any To take the silver coinage first, the fineness of became mere billon, containing: 820 of copper, degree international, the adoption of a low alloys of this metal has from very early times been 160 of lead and tin, 20 of silver; total 1,000. standard by one nation has to be followed by its computed by divisions of the troy pound, which From the time of Diocletian, when the coinage of neighbouring nations, in order to prevent loss, and weight is still retained in weighing gold and silver. silver was resumed, it was of excellent quality. A to facilitate commerce by avoiding the necessity for The Commissioners appointed in 1868 to inquire series of Roman coins of the first three centuries, tedious calculations as to the rate at which coins into the conditions of the Exchequer standards, found at Baden Baden in 1828, was analysed by may circulate in the respective countries. It is still state that "the troy pound is said to have been Dr. Walchner, of Carlsruhe, whose results may be possible, though not to the same extent, to make derived from the Roman weight of 5759-2 grains, briefly stated as follows. A coin of Heligobalus profits in the way indicated by Sir John Pettus, the 125th part of a large Alexandrian talent, this proved to be the lowest standard (505), while one of who, writing in the 17th century, observes, "it is weight, like the troy pound, having been divided Antonius Pius, which contained 913 parts of silver, good for a traveller to be skilful in different alloys, by the Romans into twelve ounces;" and they add, was the highest, coins of Commodus, Domitian, whereby, as a friend of mine told me, that he the troy weight is universally allowed to have Hadrian, and Trajan varying from standard 797 to carried out £100 with him, and by his art of ex been in general use from the time of King Ed- 890. Time will not permit me to trace the varying change in countries where alloys differed he bore ward I. The most ancient system of weights in this changes in the fineness of the coin issued in the his charge of travel and brought his stock home kingdom was that of the moneyer's pound, or the barbaric times which followed the overthrow of the again.' A well-known modern instance of such a money pound of the Anglo-Saxons, which con- Roman Empire. Judging from their appearance, system is presented by the action of the first Euro- tinued in used for some centuries after the Con- the coins present endless variations of standard. peans trading with Japan in virtue of the Treaty of quest, being then known as the Tower pound, or In view, however, of the special interest connected 1858, who, availing themselves of the fact that the sometimes the goldsmith's pound. It contained with the early British series, I may point out that gold coins of that country were current at con- twelve ounces of 450 grains each, or 5,400 grains, Mr. John Evans has clearly traced the design they siderable less than their true value in silver, bought and this weight of silver was a pound sterling. bear to the stater of Philip of Macedon, who struck the gold kobangs then in circulation for about one- The Tower pound was abolished in 1527 by a the coin in question of gold of a high degree of purity. third of their actual value, and realised large statute of King Henry VIII., which first estab- King Edward VI. improved the fineness of the profits. The actual melting of the precious aud lished troy weight as the only legal weight for gold gold currency in 1549, and in 1552 an indenture base metal is effected in small furnaces with and silver. From that time to the present was made authorising the coinage of gold both of natural draught, and the crucibles employed are our system of coinage has been based on the troy the old standards 994-8, and of the standard 916.6. usually made of a mixture of graphite and fireclay. weight." The computation of the standard fine- Queen Mary issued coins of fineness 994-8 (23 carats The capacity of the crucibles is very varied; those ness of alloys of gold is based on the singular 34gr.). Queen Elizabeth struck coins of both used in this country for melting gold hold about "carat" system of weights, the origin of which is standards. The coinage of gold of the "old 1,200oz., and the crucible for melting silver 4,000oz. popularly believed to have been derived from the standard" 994-8 was abandoned in the 12th year of Gaseous fuel is sometimes, though rarely, employed weight of an Oriental plant seed. Mr. H. J. King Charles I., and since that time the standard in mints, and I only know of one mint in which Chaney, who is intrusted with the duties of the 916-6 (22 carats fine) has alone been issued. Coins metal is melted on the open bed of a reverberatory office of Warden of Standards, informs me that made of the old standard previously to that period furnace, and then, of course, the alloy to be formed "its history is not easily traced, but that the continued to be current until the year 1732, when is only bronze. The use of such furnaces would origin of the carat is doubtless Grecian. The they were withdrawn from circulation by proclamapresent some advantages, but as a considerable ceratium was a small Greek weight." It is un- tion. The vicissitudes through which the silver amount of metal would be, temporarily at least, certain whether the use of the carat came to us coinage has passed have been greater than those hidden in the more or less leaky furnace bed, it through the Arabian alchemists or through the that have affected gold. I have selected a few becomes absolutely necessary to employ crucibles Roman mints, and the exhaustive inquiries of examples of coins issued before the Roman Cons for melting the precious metals. With regard to Vasquez Queipo do not throw much light upon the quest, and have assayed them. A coin of Burgred the choice of the base metal to be added to the point; but with regard to the supposed derivation contained only 302 parts of silver in the thousand, precious, many conditions have to be taken into of the weight from the seed or bean, Mr. Chaney while one of Ethelred was 918-4, and was probably consideration. The resulting alloy must be of good thinks "it is more probable that the Greek Keration, intended to represent the old standard of England, colour, must be ductile, and must not exhibit any and the Arab Kyrat were applied to the beans or 925. A coin of Canute proved to be of standard traces of brittleness. In the case of gold, silver seeds by the native merchants, who made them 931, which was clearly intended to represent the old forms a very ductile alloy, but then it sensibly serve provisionally as weights." It has been standard. Two separate coins of King Edward the lowers the colour of the gold. Copper, on the other necessary to offer the foregoing explanations, Confessor, assayed by me, proved to be 941, which hand, heightens the tint, and has the advantage because the expression of the varying standards of is "better" than standard; but Mr. John Evans, of yielding a durable as well as ductile alloy. A fiueness, either in the "carat and grain" system who kindly gave me one of the coins, considers triple alloy of gold, silver, and copper may be made or in the "ounces, pennyweights, and grains" of that this slight superiority to standard is due to the of delicate tints, but a triple alloy is difficult to the troy system, is somewhat obscure to those who fact of copper having been removed from the surassay, and it is undesirable to complicate the acare not familiar with their use; and although the faces of the coins by the operation of cleaning to counts of a mint by the use of two precious metals decimal system will be adopted for the purposes of which they had been submitted. Auglo-Saxon and a base one in the same alloy, therefore a single this lecture, it will be difficult to avoid references and Anglo-Norman coins are believed to have been base metal, copper, is now almost universally used. to the older methods of computation. In 1790, of the "old standard," 925, and a coin of William It has long been known that the union of two or Mirabeau, in an elaborate memoir submitted to the the Conqueror which I assayed proved to be more metals produces a result which often differs National Assembly in France, urged that the 922-8. In England, this old standard appears to more in physical properties from either of its con- decimal system should be applied to the coinage, have remained unchanged until the 34th year of stituents than they do from each other. Copper and his views were adopted in 1794. The King Henry VIII., when a great fall took place. and tin, for instance, alloyed in definite proportions, use of this system spread rapidly over the A still more rapid fall in the standard fineness yield alloys of a wide range of properties, and there Continent, but the computation of the fineness of ensued in the rest of the reign of King Henry VIII., is hardly any fact more remarkable in the whole gold alloys by the system of carats and grains sur- and in the reign of Henry VI. It fell to ite range of metallurgy than the enormous influence vived in the English Mint until 1882, when the lowest point in the 4th year of the latter monarch, exerted on a large mass of metal by a small decimal system was introduced. It may be conve- when the pound of silver contained only Soz. of quantity of another metal or metalloid. From the nient to begin the history of the alloys used for fine silver, and 9oz. of base metal, that is, the Mint point of view, the properties which it is most coinage with the employment of the natural alloy standard, expressed decimally, was only 250. desirable to secure are-1. Ductility; 2. Durability; of gold and silver, to which the ancients gave the Strangely enough, this base coinage was projected 3. Uniformity of composition. In addition to these, name of electrum, native gold being always asso- with a view to secure by the transaction the alloy is expected to be senorous, that is, the ciated with silver, which is sometimes present in the sum of £160,000, to be devoted to the coin struck from it must have the true "ring; sufficient quantity to sensibly lower the colour of restoration of the standard generally. Half this and, finally, it must possess exactly the degree of the more precious metal, and to cause the gold tint sum appears to have been actually obtained. viscosity which will enable it to flow, under pres- to disappear almost entirely when it exceeds one- The restoration of the standard of the silver begun sure, into all the fine lines of an engraved die, third part of the mass. Dr. Schliemann describes in the reign of King Edward VI., was completed while at the same time the metal must have three pale yellow rod-like bars, each 4-33in. long, by Queen Elizabeth, and it has not been since desufficient rigidity to retain its impression when provided with fifty to sixty equi-distant horizontal based. I have thus attempted to trace the history submitted to rough usage. With regard to the incisions, at right angles to the length of the rods, of the gold alloy of standard fineness 916 6, and the sonorous property of the alloys used for coining, if which probably indicated their value, and facili- silver one of 925, the alloys used in this country for two rods, one of pure silver, and the other of the tated their sub-division into definite portions. Dr. the gold and silver currency, and as the gold retoy of silver and copper, known as standard Schliemann kindly permitted me to analyse a small presents a large proportion of the coinage of the portion of one of these rods, which was found to world, it may fairly claim to be the most importsilver, be hung close together, one will contain 651 parts of gold and 334 parts of silver in ant gold alloy in existence. England is not the when struck, while the other gives a 1,000 parts, and small quantities of copper and only country in which it is retained; the explana indistinct sound. The best indicati lly tion of its existence in other countries is found in copper, and zinc has been extensively employed in the fact that standard 916-6 is the metric equiva- Switzerland for the manufacture of subsidiary coins. lent of 22 carat gold, and, as the carat system has A very low alloy of silver and copper has long been been in use from early times, it is natural that employed for coins of small value; such an alloy is many nations should have originally adopted the called billon, and was formerly widely adopted on convenient proportion presented by 3, or 1, the Continent generally in modern as well as ancient which this alloy represents, and it has, accordingly, times. The precious metal contained in the mass is held its own in British India, Russia, the Turkish not present in sufficient quantity to give the alloy Empire, Portugal, Persia, and with a slight the colour of silver, and therefore the copper is variation in Brazil. As it will not be possible to removed by the action of a solvent from the surface examine the history of the alloys at length, attention of the "blanks" before they are coined; but this must be limited to the more important ones, of layer of silver soon wears off when in circulation, which the alloy containing 900 parts of gold in the and the coins assume the normal tint of the alloy 1,000 parts demands special notice. The coins in from which they are made. The advantage of emcirculation in France from the beginning of the ploying precious metal in this way consists in the 17th to the end of the 18th century varied in fine- possibility of striking subsidiary coins of some value, ness from 900 to 982; for instance, the louis d'or of but of comparatively small weight. The alloy next King Louis XIII. were 22 carats fine, the ecus d'or in importance to those we have hitherto considered of Louis XIV. were 23 carats, while the lys d'or of is bronze, which, as has already been stated, played the same monarch were 23 carats and one-fourth of an important part in ancient currency. Its modern a grain. When, however, the decimal system of use on an extended scale is due to the Government weights and measures was fairly established, coins of the late Emperor of the French, Napoleon III., were issued in conformity with it. The law of the by whose direction the old sous circulating in France 28th Thermidor, An. III. (1796), fixed the franc as afforded the basis for a triple alloy, containing 95 the monetary unit, and enacted that the standard parts of copper, 4 of tin, and 1 of zinc, the weights fineness of the silver coins should be 900, the of the respective coins of one to ten centimes being weights as well as the fineness of the coins being a gramme for each centime. The law regulating strictly in accordance with the decimal system, this coinage was passed by the Assembly in May, although round numbers were not secured in the 1852, and the issue of bronze from that time up to respective weights of the coin. Eight years later, the year 1868 amounted to no less than 59,300,000 the law of the 7th Germinal, An. XI. (28th March, francs. All the facts connected with this coinage 1803), prescribed the coinage of gold pieces of 20 have been elaborately described by M. Ernest francs, the standard of which was also 900. A Dumas. It is an extremely durable alloy, subsequent law, the result of the recommendations as will be shown in the fourth lecture. of a committee appointed by the French Senate, Its coinage was undertaken in England in directed, on the 25th of May, 1864, that pieces of 1861, by the advice of the late Prof. Graham, Master 50 and 20 centimes should be of standard 835; and of the Mint, and the amount of bronze coin now in on the 14th of July, 1866, the standard of fineness circulation is estimated to be about 300 tons. Brass of pieces of one and two francs was also reduced was extensively used by the Romans for subsidiary to 835. By the Monetary Convention of the 23rd coins, and, in fact, silver does not appear to have December, 1865, concluded between France, been employed until "the first Punic war, Belgium, Italy, and Switzerland, the standards of 269 B.C.' Savot mentions the use of a triple fineness above described were adhered to. Several alloy of copper, zinc, lead, and a small quantity other countries, notably Roumania, Servia, Greece, of tin, to which the name of potin was given Scandinavia, and most of the republics of South and Lenormant states that it was only used America, have partially adopted the same monetary for money by certain tribes of Gaul between system. In Germany, in virtue of the laws the wars of Cæsar and the organisation of the of the 4th of December, 1871, and the 9th of Gaulish provinces by Augustus. The coins were July, 1873, the standard fineness of both gold and always cast, and prove, on analysis, to contain :silver has been fixed at 900. In the United States 60 of copper, 20 of lead, 10 of zinc, 10 of tin; total, of America the use of the alloy 900 fine has been 100. The use of nickel is extremely ancient. Dr. confirmed, for both gold and silver, by the Coinage Walter Flight, F.R.S., has shown that coins of the Act of the 12th of February, 1873. It will be evi- 2nd century B.C. were struck in an alloy condent, from the foregoing remarks, that the two taining:-77-85 of copper, 20-038 of nickel, 0.544 really important alloys used for coinage of gold of cobalt, 1048 of iron, 0.038 of tin, trace of silver, have respectively the standard fineness 916.6 and 0.090 of sulphur; total, 99 343. Pence and half900, while for silver coins the standard 900 is now pence to the value of £3,000 were coined at the more widely used than any other, England alone Mint in the years 1869-71, for use in the colony of employing 925, which still maintains the connec- Jamaica, of an alloy containing 75 of copper and tion with Saxon coins. The alloys to which refer- 25 of nickel; but when a further coinage of nickel ence has hitherto been made have been simple of the nominal value of £500 was required, Mr. ones of two metals. In the case of gold coins, the Fremantle reported that the charge to the colony second metal contemplated by law was copper, but of Jamaica for the metal alone "would exceed the silver was, in many cases, used, either to the ex- nominal value of the coin," a fact which points to clusion of copper, or in conjunction with it. The the difficulty of determining the weight that may Australian gold coins first issued contained a con- be safely given to the individual pieces of a token siderable proportion of silver, as their colour showed, coinage when the metal employed is liable to but in all the examples given the use of triple serious fluctuations in commercial value. Pieces alloys has rather been the result of accident than of 5 and 10 centimes of the same alloy have long of design. It will now be necessary to con- been in circulation in Belgium. In Germany also sider triple or complex alloys at some length. In the pfennige are of this alloy, and it is also emearly times, when complex ores were treated by ployed for the subsidary coinage of Brazil. Certain metallurgists who may have possessed considerable American nickel coins contain 12 per cent. of nickel skill, without knowing how to insulate each of the and 88 of copper. The important contributions of metals present in the ore, singular admixtures have Herr Fleitmann to the metallurgy of nickel have been obtained as the result of the operation. A rendered it possible to use the pure metal for very experienced copper smelter, Mr. Tyrell, of coinage, and the 20-rappen pieces of Switzerland Swansea, has shown that it is only necessary to are now struck in nickel without alloy. The claims smelt copper pyrites with a small addition of an ore of platinum to be used for coinage did not escape which contains tin, in order to obtain bronze of the M. Rochon, and the fact is remarkable, considering composition frequently met with in ancient imple- how comparatively rare the metal was when he ments or weapons. Numerous instances of the wrote in 1786. With regard to metals which have involuntary use of complex alloys for coinage not as yet been employed for coinage, I would might be given, but the best example is probably direct your attention to those very light specimen presented by the coins of the early Britons, which coins of pure aluminium, and of aluminium alloyed were of copper alloyed with 20 to 25 per cent. of with 2 per cent. of nickel, for which I am indebted zine and 5 to 11 per cent. of silver, together with to the distinguished metallurgist, Mr. G. Matthey, small quantities of gold, lead, and tin. Mr. John F.R.S. Evans has pointed out that the Saxon stycas range through a wide field of alloys, and may in some cases have been formed by melting together the coins discovered in "hoards" of Roman coins with, of course, very variable results. In the case of gold, such triple alloys have been used but seldom. A modern instance in which their use was suggested is presented by the triple alloys of gold, copper, and zinc, prepared in 1873, by Mr. Péligot. He showed that an alloy containing 58.1 per cent. of gold, 361 of copper, and 5-8 of zinc is of good colour, can be readily worked, and possesses the advantage of being decimal as to weight. Péligot also suggested the use of three alloys of silver, copper, and zinc, containing respectively 5, 10, and 7-2 per cent. of zinc, and 90, 80, and 835 per cent. of silver, the rest being, in each case, copper; and he also described three simple alloys of silver and zinc, containing respectively 5, 10, and 20 per cent. of zinc. Triple alloys, in which silver is the main constituent, have often been used. A singular alloy of silver, Boiled Lettuces.-The lettuce is a neglected vegetable, although it constitutes a prominent ingredient in every good salad. At one time the lettuce was supposed to possess soporific properties, but of late years it has, perhaps too hastily, been disestablished as a drug in the repertory of the therapeutist. Some are now strongly insisting that lettuces should be used more generally as food, and suggesting that they ought to be boiled, after which treatment they are said to be as palatable as spinach. If this be the fact, it is worth knowing, as spinach is necessarily excluded from the diet of the oxaluric patient, and it is precisely in this class of cases the soothing properties of the lettuce, if it have any, would be valuable.-Lancet. A PONDEROUS ledger has just been turned out of the Government bindery for the use of the United States Sub-Treasurer at New York, which weighs 871b., is Sin. thick, and measures 21 by 32in. SCIENTIFIC NEWS. AMONGST recent deaths in the scientific Swedish geometrician August Pasch, at the age of fifty-one; of Dr. Lar Magnus Larsson, the botanist, tutor of the high school, Carlstad, at the age of sixty-two; and of Prof. Sten Stenberg, the chemist, in his 60th year. All these were Swedes. world we have to announce those of the The comet announced last week in Dun Echt Circular, No. 86, was observed at Algiers, on July 25, 9h. 1m. 26s. G.M.T., its place being R.A. 16h. 9m. 128., S. Dec. 37° 24'. 14". From Circular No. 87 we learn that the three places mentioned last week were inadvertently telegraphed as part of the message, whereas they were merely places to which it was to be forwarded. From Prof. Adams's report to the Senate of Cambridge University, as to the proceedings in the observatory during the year ending May 26, 1884, we learn that the observations during the year were made almost exclusively with the Transit Circle. The total number of observations made with this instrument during the interval, for determinations of Right Ascension and North Polar Distance is 2,305. These include 588 observations of clock stars; 69 observations of Polaris at the Upper Transit, involving 157 circle readings, and the same number at the Lower Transit, involving 161 circle readings; and 1,579 observations of Zone-stars which were made on 100 nights. For instrumental adjustment, the Nadir Point was observed 180 times, the Level 180 times, and the Collimation 200 times. For the Standard stars the observations in Right Ascension are reduced to the end of 1883, and those in North Polar distance are nearly completed to that date. For the Zone-stars the True R.A. and True N.P.D. are obtained to the end of 1881: the Mean R.A. and Mean N.P.D. to the end of 1877. The calculation of the reduction to Mean place from Apparent is completed to the end of October, 1881, and nearly completed for the remainder of the year. The constants for Collimation and Level, and the Nadir Points, are obtained up to May 22, 1884; and, the observations for errors of division are completely re The summer meeting of the Institution of Mechanical Engineers will commence at Cardiff on Tuesday next, when the president, Mr. I. Lowthian Bell, F.R.S., will deliver his inaugural address. The following papers are down for reading:-"On Recent Coal Shipping Machinery at the Bute Docks, Cardiff," by Mr. J. M'Connochie, of Cardiff; "Description of the New Locomotive Running Shed of the Taff Vale Railway, Cathays," by Mr. C. H. Riches, of Cardiff; " 'Description of the Francke Tina,' or Vat Process for the Amalgamation of Silver Ores," by Mr. E. P. Rathbone, of London; "On the Use of Petroleum Refuse as Fuel in Locomotive Engines," by Mr. T. Urquhart, of Russia; "On the Causes and Remedies of Corrosion in Marine Boilers," by Mr. J. H. Hallett, of Cardiff; "On the Mineral Waggons of South Wales," by Mr. A. Slater, of Gloucester; "On the Application of Electro-Magnets to the Working of Railway Signals and Points," by Mr. J. A. Timmis, of London. We have heard so much about the utilisation of Niagara that it will be interesting to learn what is actually done at the great waterfall. At a recent meeting of the American Association of Civil Engineers, Mr. B. Rhodes said that the average flow of the river according to many careful measurements is 275,000 cubic feet per second. The fall in the river through the rapids immediately above the fall is 65ft. The height of the fall is 165ft., making a total of 230ft.; thus we have for the whole power 7,000,000 horse power. To utilise this amount of power by water-wheels; to generate electrical currents, and transmit to various cities within 500 miles, residue of aluminium. When the fused mass is would necessitate a plant representing at least The buildings for the Philadelphia Electrical Exhibition are practically complete, and there is reason to believe that, despite the fall in the commercial value of Electric Lighting, &c., Companies, the exhibition will be one of the most interesting yet held. Edison, it appears, intends to show a 30-ton dynamo, and a notice has been prepared cautioning visitors not to approach it too closely. The United States Electric Light Co. will endeavour to outshine Edison, and at any rate will have a fine exhibit. In Reynier's new book on Galvanic Batteries, he compares the Daniell, the chromic acid, and the Lalande-Chaperon cells, to the disadvantage of the last named. He finds the verdigris Daniell the cheapest, and the Lalande-Chaperon the dearest, its working cost being given as about 58. per horse-power per hour. As a result of his experiments with accumulators, he finds that the cost of a horse-power per hour is 1s. ld, while horses cost 1s. 7d. His calculations are based on experiments made with accumulators in tramcars, &c. of the type of o Ceti; and if we accept this explanation, we need not even seek an instrumental cause for Mr. Burnham's failure to perceive what was seen not only by alessrs. de Boe, Slack, Prince, &.-all practised observers-but was picked up by young Von Ertbon without difficulty, albeit he did not even know what the Pole Star was! I am entirely in accord with "Garrison Gunner" in his assertion (in letter 23005, p. 437) that EDITOR."electricians will find it very difficult to explain" the attraction of a flash of lightning by the steel frame of a pair of spectacles!-especially as this same flash (which obviously didn't know how to conduct itself) made no attempt to reach Earth through the body of its fair victim. The fact of its striking her at all, though, in what I may call so utterly purposeless a way, may only have indicated that (in the invariable words of counsel in actions for breach of promise of marriage) she "is a lady of con-sid-e-ra-ble per-so-nal attractions." [We do not hold ourselves responsible for the opinions of ••• In order to facilitate reference, Correspondents, when "I would have everyone write what he knowe, and as much as he knows, but no more; and that not in this only, but in all other subjects: For such a person may have some particular knowledge and experience of the nature of such a person or such a fountain, that as to other things, knows no more than what everybody does, and yet, to keep a clutter with this little pittance of his, will undertake to write the whole body of physicks; a vice from whence great inconveniences derive their original" -Montaigne's Essays. In reply to "J. A." (query 54201, p. 450), I know of no single work on astronomy which goes in the way he desires-over the whole ground covered by Herschel's "Outlines." For example, the deductions in Herschel's Chapters XII., XIII, and XIV. demand a familiarity with the higher analysis, and an acquaintance with the more abstruse branches of mathematics generally, for their numerical application, such as would preclude the treatment of the subjects they discuss in conjunction with others. Loomis's Treatise on AstroCOLOUR-BLINDNESS AND STELLAR nomy" is, however, an excellent book for giving the student an insight into the application of mathematics to the solution of all the problems with which the practical astronomer has to deal, and so far follows the "Outlines" as to combine a mass of descriptive astronomy with the formulæ and worked examples which give it such value. By all means get it. CHROMATICS COMBINED STAR MATHEMATICAL ASTRONOMY BELGIAN RESULTS OF THE LAST TRANSIT OF VENUS-VENUS IN INFERIOR CONJUNCTION-THE GROUP B IN THE SOLAR SPECTRUM HUYGHENIAN EYEPIECE. [23059.]-THE recent investigations of Lord Rayleigh on the subject of colour-blindness would seem to possess peculiar interest for students of sidereal The adjudicators in the Ellis Lever competition chromatics. In conjunction with Mr. Offert, Lord for the prize of £500 for a new safety-lamp, have R. has devised a piece of apparatus in which, by been unable to make any award, because there is double refraction, he causes two spectra to overno lamp that perfectly fulfils the whole of the lap. The subject of the experiment then looks at conditions. Among the best (there were four the resulting colour, and describes it as it appears electric lamps and 104 oil lamps), two the adjudi- to him. One of Lord Rayleigh's results is that the cators regard as deserving of special mention-majority of people require only half as much red viz., the Marsaut, with three gauges, and the lamp designed by Mr. W. Morgan, of Pontypridd. The adjudicators were Thos. Burt, M.P., Sir F. A. Abel, Profs. Gryll Adams, and S. P. Thompson. The Government have directed Dr. Klein, F.R.S., and Dr. Heneage Gibbes to proceed to India, and pursue a scientific inquiry into the nature of cholera. They will, it is understood, act in conjunction with the Commission appointed by the Indian Government. M. Paul Bert has addressed some words of common sense to his countrymen in a series of articles on "Cholera," and concludes that they must give up supposed precautionary measures which are merely troublesome without being of use. Meantime, the Brindisi passenger route to and from India has been closed by the Italian Government, who cannot apparently see the futility of quarantine measures as they are carried out on the Continent. MM. Mallard and Le Chatelier publish in the Annales des Mines a memoir "Sur les Températures de Combustion et les Chaleurs Spécifiques des Gaz aux Températures Elevées." This memoir is the third of a series, the first being on the "Températures d'Inflammation des Mélanges Gazeux," and the second "Sur la Vitesse de Propagation de la Flame dans les Mélanges Gazeux." The whole presents the most extensive scientific examination of the explosive atmosphere of coal-mines which has been given to the public. In the Annales de L'Observatoire Royal de Bruxelles, Tome V. for the current year, M. J. C. Houzeau, the Belgian Astronomer_Royal, gives the results of the observations of the Transit of Venus of 1882, December 6th, made at the Belgian stations by the aid of heliometers, the halves of whose object-glasses were of unequal focus. As everyone knows, in the ordinary form of heliometer the object-glass is cut in half, and we then get two images of identically the same size at the same focal distance. If, though, the two half-lenses belong to objectives of different foci, we get two unequal images that we can superpose by placing the lenses at the proper distances on the optical axis of the telescope, so that the images formed by them respectively shall come to a focus in the same he does himself. By far the most common form of piece. Thus the only difference perceptible to the in the mixed spectra to turn yellow into green that plane, and hence be observable with the same eyecolour-blindness is blindness to red. Dr. Guthrie, observer is, that he gets one big image and one who is so afflicted, is more than usually sensitive to little one. Now, what M. Houzeau did was so blue light. Others have been found with the same to proportion the foci of his half-lenses that he got abnormally acute perception of red. The father of a small image of the Sun, very nearly equal, indeed, maker, suffered from the very rare defect of being Sun was slightly the smaller of the two, so that it Mr. Stanley, the eminent mathematical instrument to the large image of Venus. The image of the colour-blind to green. The importance of these could be centred upon the very slightly larger black researches in connection with star colours and their disc of Venus with the greatest accuracy. This supposed variation, can hardly be over-estimated. simple arrangement enabled It is a most familar fact that certain astronomers of measures of the distance between the centres of a large number speak of stars as "red," which certainly present the Sun and Venus to be taken during the Transit. no such tint to the large majority of observers. At St. Iago, in Chili, they secured 606 such (if I may coin such a word) of every one engaged they got fewer, as clouds were drifting over the Hence the importance of testing the colour-capacity measures in 5h. Sm. At San Antonio, in Texas, in the determination of star colours. been done hitherto, we might very probably have scribe either the observations themselves or the way Had this sky. It is, however, less my purpose here to deheard less of the alleged startling changes of colour of making them, than to give their results. In effect, in certain bodies in the heavens than we have done. then, M. Houzeau finds the Equatorial horizontal I had written the above paragraph before seeing parallax of the Sun to be 8-911", with a probable the interesting letter of Mr. B. J. Hopkins (23003) error of 0.084". This would place the Earth at the colours of a close pair of approximately equal on p. 436. I have never made the combination of a mean distance of 91,727,000 miles from the Sun. double stars the subject of experiment; but, reasoning à priori, it would certainly seem that the result anticipated by Messrs. Baird Gemmill and Hopkins must accrue. Might not this be tested by shape of an ordinary donble-image prism fitted in a modification of Lord Rayleigh's apparatus, in the the eye-cap of an eyepiece of sufficient power to fairly separate the components of the star? There would be no insuperable difficulty in constructing such a prism so that it should cause the images of two stars at a given distance to overlap; but of course its use would be confined to objects separated by a fixed and definite angular interval. Even with this limitation, I am sure that it would furnish the means for prosecuting a most instructive inquiry. some Observers who have devoted attention to the appearance presented by Venus when in inferior conjunction, will probably read with interest a paper by. Ó. Callandreau, in the Bulletin Astronomique of the Paris Observatory for May, 1884, of conjunction of 1882. It is illustrated by a series of his own observations of that planet during the astonishing woodcuts representing the illuminated crescent proper, lying, as it were, between two concentric, but much fainter, crescents, or ares of light, which seem to have grown with the growth of the actual illuminated limb. M. Callandreau observed at Pieton Villa, near Port-su-Prince in Haiti, 328 yards above the sea-level, with a 6-3 inch equatoreal, and in an atmosphere of the most perfect purity and calu. He tells us that he used various eye-pieces To obtain aluminium, according to the The letter of Mr. Binns (23001, p. 436) will, I magnifying from 100 to 300; but without eliminatChemiker Zeitung, ferro-silicium is mixed with hope, attract attention. The story told by so ing these extraordinary appendages to the crescent fluoride of aluminium in equal proportions, and skilled, conscientious, and accurate an observer as of the planet. I speak with some reserve; but, the mixture is exposed to a fusing heat. The de Boe is not to be pooh-pooh'd, even upon the looking at M. Callandreau's sketches, they strongly materials decompose each other, and volatile admittedly great authority of Burnham. That suggest the idea to me that his object-glass produced fluosilicium with iron and aluminium are probecause an object, or objects, are invisible in antese curious luminous arcs. Of course if these duced, the two latter bodies being alloyed Sin. telescope they never can have been seen with were seen in any other telescope, my theory at together. a smaller instrument, and, ergo, do not exist at all, once falls to the ground; but if M. C. was the sole In order to extract the valuable will scarcely satisfy anybody who has ever human being who witnessed this abnormal and aluminium, a copper alloy is formed by melting had any experience with one of these monstrous surprising phenomenon, I should certainly be the iron alloy with metallic copper; by reason of refractors. To my mind, Mr. Binns' observation strongly tempted to look for its origin in the obthe greater affinity of the copper for aluminium would rather seem to point to the fact that Polaris jective of his equatoreal-and there alone. this is secured, leaving with the iron only a slight may have one or two comites, which are variables In the same number of the Bulletin there is an I have endeavoured to show elsewhere that the large inclosed area, which includes Wollaston B and extends some miles to the north of it, is not, Y CASSIOPEIA-AFTERGLOW. as Mädler describes it, merely the result of a fortuit- [23063.]-IN letter 22753 (p. 252, May 23), Mr. ous arrangement of ridges, but a true ring-plain, Sadler refers to my conjecture that either 3 607 with a very concave floor and a good-sized central or Arg. (-0°) 2600 may be variable, and remarks mountain. On the morning of March 8 the interior" but I have very little faith myself in the variawas about one-half filled with shadow, in which bility of either." The estimates which Mr. Sadler the northern portion of the ring of Wollaston B gave on p. 335, Vol. XXXVII., certainly seem to was involved. Two craterlets were visible on the indicate variability; for while both stars were western wall, though only one, the more southerly shown to be entered in the Durchmusterung at 9-2, and the brighter, is shown in the drawing, as I it was shown that in the Munich Zones 3607 is 8mag. Omitted to insert the other at the time, though it and Arg. (-0°) 2600 10mag. The tantalising and, in was certainly seen. The irregular character of the general, most unastronomical weather we have had |