THE MONTH: SCIENCE AND ARTS.

In 1845 the late Professor Faraday delivered a lecture on the solidification of gases at the Royal Institution, and demonstrated his facts by experiments as interesting as they were successful. Under his skilful manipulation a tube filled with olefiant gas, quite invisible, was seen to become partially filled with a colourless liquid, which was the gas in a condensed form. Two conditions were shewn to be essential to the result‒extreme pressure, and extreme cold. The pressure was obtained by strong mechanical appliances, and the cold by means of solidified carbonic acid, which looked like lumps of snow. In this way the lecturer made clear to a general audience the process by which a number of gases had been brought into a liquid or solid form; and he stated that he had ‘hoped to make oxygen the subject of the evening’s experiment, but from some undetected cause it had baffled his attempts at solidification.’ Nevertheless, he looked forward to the time when not only oxygen, but azote and hydrogen would be solidified, and he agreed with Dumas, of the Institute of France, that hydrogen would shew itself in the form of a metal.

Faraday’s anticipation is now realised in one particular, for oxygen has been liquefied. This achievement is due to the enlightened and persevering efforts of Mr Pictet, an able physicist of Geneva. Working with apparatus capable of resisting a pressure of eight hundred atmospheres, and a temperature sixty-five degrees below zero (centigrade), he succeeded in converting oxygen (invisible) into a visible liquid which spouted from the tube in which it had been inclosed for experiment. It is a feat which involves important consequences for science. It is a further confirmation of the mechanical theory of heat, according to which all gases are vapours capable of passing through the three states‒solid, liquid, and gaseous. Geneva winds up the year with a fine scientific triumph. Will Albemarle Street supplement it by liquefying or solidifying azote and hydrogen? Just as these lines are going to press we hear a rumour that it has been done by a Frenchman at Paris.

Experiments have been made to measure the sound-impulse produced in a telephone by ordinary speaking; but it is too feeble to excite even a delicate galvanometer. But a slight swing of the free end of the instrument affects the needle, which moves in a different direction according as the swing is south, north, west, or east. There is no doubt, as we observed in a recent paper on the subject, that in the behaviour of the telephone and the phenomena of its currents scientific men have a promising subject of inquiry. Meanwhile, as explained at the end of this article, the notion that it would at once supersede other forms of telegraphy or telephony will abate. A telephone has no advantage over a speaking-tube within the distances where a tube is available. Moreover the needlessly high price at which it is to be sold will be an effectual bar to its general use. To ask thirty-five pounds and twenty-five pounds for an article that could be sold at a profit for so many shillings, is not and ought not to be the way to commercial success.

It is stated in a French scientific periodical that underground water may be discovered by observing the quivering of the air on a clear calm summer afternoon when the sun is low. If a well be dug at the spot where the quivering appears, a supply of water will, as is said, there be found. And as regards the influence of trees on moisture, careful observation has confirmed the theory that more rain falls on forests than on open plains; and comparing different kinds of trees it is found that the pine tribe get more water and retain more than leafy trees. Hence, it is said, pines are the best defence against sudden inundations, and the best means for giving freshness and humidity to a hot and dry climate such as that of Algeria, where attempts at amelioration have been made by planting, and by the digging of artesian wells.

Readers of this Journal will not be ignorant of the health-imparting properties of the Australian gum-tree, or eucalyptus, nor that the fir and pine possess similar properties, but in a minor degree, yet still sufficient to enhance the title to salubrity of certain watering-places. Mr Kingzett, an ingenious and persevering chemist, had tried for a long time to discover whether the active atmospheric element, ozone, was evolved from the leaves of plants, and was forced to the conclusion that the element produced was not ozone, but peroxide of hydrogen. He then experimented on oils of different kinds, and found that they absorbed oxygen rapidly, and were thereby in some instances transformed into new substances. Among them all turpentine proved to be the best absorber; and it appeared on further experiment that while one portion became resinified, another portion was converted into peroxide of hydrogen and camphoric acid. The natural conclusion from this result was that the eucalyptus and the pine owe their salubrious properties to the presence of these two substances; or rather to the ‘terpene,’ or principle of turpentine, with which they are imbued. This point established, measures were taken to produce the sanifying substances on a large scale; and now a company owning a manufactory in the east of London advertise that they are ready to supply the new disinfectant under the name of Sanitas in any quantity. It is not poisonous, will not stain the materials to which it may be applied, can be used as a wholesome scent, and is efficacious in preserving articles of food. The process of manufacture is ingenious, and is so combined that there is no waste of turpentine even in the form of vapour; but of the details we need not attempt an explanation here. Suffice it that Sanitas, with full description of its virtues, is now largely advertised in the public journals.

Professor Galloway, of the Royal College of Science, Dublin, has published a pamphlet in which he states that salted meat is unwholesome, and produces scurvy, because by the process of salting the meat is deprived of important constituents, notably phosphate of potash. He says that if this salt were eaten with the beef served out on board ship, the meat would be nutritious, would not occasion scurvy; and he calls on the Admiralty to test his view by actual experiment.

What a convenience it would be if all the street lamps of a town could be lighted and put out at once! Mr Lane Fox has proved at a commercial station in the neighbourhood of Fulham that it can be done. All the lamps are connected by wires overhead or underground; to each burner is fitted an electro-magnet composed of a coil of wire round a soft iron core, and above it hangs a movable magnet. The ends of the connecting wires are attached to or detached from a battery at pleasure. When the gas is to be lighted, a current is sent through the wires; the electro-magnet on each burner is excited; the movable magnet swings round, and turns on the gas; a current from a powerful coil is then sent through the wires, and produces a spark at each burner, and thereby lights the gas. The putting out is effected by a reverse current. From twenty to forty lamps have been thus treated, and with entire success; and it is thought that three hundred might be included in the circuit with a like satisfactory result.

Thus in order to light up London or any other large town, the lamps would have to be divided into groups of three hundred. The lamplighter, or man in charge of the battery, would of course require to know that none had been missed, and this could be made certain by placing the first and last lamp of the group within sight of his station. If they are alight, then all are alight. The practicability of the operation appears therefore to be settled. The next question is‒Will it prove a saving to the ratepayers?

Complaints that ordinary gas-light is not so brilliant as it ought to be, are often heard, and not without reason. The Pure Carbon Gas Company claim for their gas that it is not open to the objections urged against other gas. The process of manufacture has the merit of being very simple, and free from the usual noxious results. At a demonstration made a few weeks since, proof was given that but little space and little skill are required in the manufacture. The tar formed during the process, instead of being carried away as at present, is passed back into the retorts, whereby, as is said, three thousand feet more of gas can be produced from a ton of coal than by the ordinary process. An arrangement is introduced which separates the ammonia and the sulphur, and in consequence this pure carbon gas has but little smell. Ordinary gas is passed as good if it contains not more than twenty-five grains of sulphur to the hundred feet: the quantity in the new gas is less than three grains. We are told that the cost of manufacture is not more than eighteenpence the thousand cubic feet, that it does not require skilled labour, that in consequence of its freedom from smell it could be carried on in a ship or in a house, while its simplicity renders it applicable to villages where at present there are no public lights. The Collinge Engineering Works, Westminster Bridge Road, are mentioned as the place where the demonstration above described was given.

With a view to account for the presence of mineral oil underground in certain parts of Europe and in Pennsylvania, some ingenious persons have assumed that the oil is a decomposition-product of long-buried organic remains. But the answer to this is that the oil is found in very old strata ‘where but few organic remains can have existed.’ Mr D. Mendelejeff, a foreign chemist, having visited the Pennsylvania wells, puts forward his opinion on this interesting question: The substance of the earth having been condensed from vapour, ‘the interior of the earth must consist largely of metals (iron predominating) in combination with carbon. Wherever fissures have been produced in the earth’s crust by volcanic action, the water, which of necessity made its way into the interior, and thus came into contact with metallic carbides at high temperatures and pressures, must have given rise to saturated hydrocarbons, which have ascended in the form of vapour to strata where they condensed,’ and thus formed the oil.

Captain Calver, R.N., has by command of the Admiralty surveyed the Thames below Woolwich to ascertain whether the discharge of the sewage of London into the river has created obstructions in the channel. The captain has published his report, and a very discouraging report it is, for it makes known that shoals have formed, and are forming, which in course of time will completely stop the navigation of the river. In this we have a proof that it is a mistake to send the solid portion of sewage into a stream, in the hope that it will be effectually carried away by the tide. It is not carried away; but is deposited at the bends, and in the eddies, with detriment to health as well as to the water-way.

Engineers who contend that none but neutralised liquid sewage should pass into a river are manifestly in the right. To discharge the solids is a waste as well as a mischief; and if it goes on, the whole of the land will some day be utterly starved for want of nitrogen. Some theorists argue that it won’t pay to attempt to convert the solids into a fertilising material. The answer to this is the experience gained at Aylesbury, where the solid part of the town sewage is separated from the liquid by precipitation; is converted into a fertiliser, part of which is used on the town-farm, and the surplus, in the form of a dry, scentless powder, is sold at three pounds ten shillings the ton. A single grain of oats, sown on land treated with this powder, produced seven thousand grains from one root, and other grains yielded varying numbers down to two thousand. The powder on analysis seems poor; but its richness of productive power may be judged of from the foregoing statement.

A new process for making sulphate of soda has been invented by M. Fournier, a Frenchman. It leaves behind as waste liquid a large quantity of a certain chloride, which turns out to be excellent for the precipitation of sewage. Hence it appears that nature and science combine to shew how the fertility of the land and the free channels of rivers may alike be maintained. The process has been patented in this country, and if all go well we may hope, in time, to hear that the sewage of London, instead of filling up the bed of the Thames, is increasing the fruitfulness of fields, gardens, and meadows in Essex and Kent.

Meteorologists, in their review of the weather, inform us that in the gale on the 11th of November last, the barometer was lower, the wind stronger, and the rainfall greater, than on any other day in the year. The mean velocity of the wind was thirty-eight miles an hour; and the rainfall in twenty-four hours amounted to a little more than an inch and a half. The fall for the whole month was in Sussex, eight and a quarter inches; in Cumberland, nine and three-quarter inches; being, as regards the Sussex gauge, more than five inches above the average of the previous ten years. The total rainfall in eleven months, January to November, was thirty-three and one-third inches: a remarkable excess over twenty-eight inches, which is the usual average for the whole year. For those who are curious in comparisons we take a fact from the weather-records of New South Wales: at Newcastle in that colony there fell on March 18, 1871, more than ten and a half inches of rain in two hours and a half.

Two official papers published in India further discuss the question‒sun-spots and rainfall. ‘The Cycle of Drought and Famine in Southern India,’ contains a statement of the argument by Dr W. W. Hunter, and the conclusions to which he has arrived. These are: ‘That although no uniform numerical relation can be detected between the relative number of sun-spots and the actual amount of rainfall, yet that the minimum period in the cycle of sun-spots is a period of regularly recurring and strongly marked drought in Southern India‒That apart from any solar theory, an examination of the rain registers shews that a period of deficient rainfall recurs in cycles of eleven years at Madras ... that the statistical evidence shews that the cycle of rainfall at Madras has a marked coincidence with a corresponding cycle of sun-spots ... and that the evidence tends also to shew that the average rainfall of the years of minimum rainfall in the said cycle approaches perilously near to the point of deficiency which causes famine.’ The average is, however, above that point; and though droughts and famines may recur in the cyclic years of minimum rainfall, the evidence, in Dr Hunter’s opinion, is insufficient to warrant the prediction of a regularly recurring famine.

The observations on which these conclusions are founded include sixty-four years of the present century: too short a period on which to build a theory; but as no records exist earlier than 1810, it is by future observation only that the conclusions can be tested. Meanwhile meteorological observers will be watchful, especially of the rainfall, for India is a country which affords singularly favourable opportunities for a comprehensive system of observations.

The other paper referred to above is by Mr H. F. Blanford, Meteorological Reporter to the government of India. He points out that Dr Hunter’s views apply exclusively to Southern India, and that in Northern India famines are most frequent at the epochs of most sun-spots. This lack of agreement between two competent authorities shews how great is the need for a lengthened series of observations.

In the recent Arctic Expedition twenty-five species of fossil plants were discovered in Grinnell Land by Captain Feilden. They are of the period described by geologists as Miocene, and can be identified with species of the same period found in Europe, in North-western America, and in Asia. Among them are two kinds of Equisetum, poplar, birch, elm, and pine. It was suggested at a meeting of the Geological Society that the bed of lignite in which these remains were met with was in remote ages a large peat-moss, probably containing a lake in which the water-lilies grew, while on its muddy shores the large reeds and sedges and birches and poplars flourished. The drier spots and neighbouring chains of hills were probably occupied by the pines and firs, associated with elm and hazel. Among all these which indicate a primeval forest, the only sign of animal life discovered was a solitary wing-case of a beetle.

When water-lilies were growing in that now desolate region, fresh-water must have filled the ponds and lakes. Captain Feilden’s discovery may be taken as additional evidence of a change of climate, which the palæontologists and physicists who are now discussing that interesting question will not fail to make use of on fitting occasion.

A few years ago the British Association appointed a committee of eminent mathematicians to consider ‘the possibility of improving the methods of instruction in elementary geometry.’ The Report of this committee was published in the stout volume which contains the account of the meeting held at Glasgow. It states that the main practical difficulty in effecting the improvement is ‘that of reconciling the claims of the teacher to greater freedom with the necessity of one fixed and definite standard for examination purposes;’ that ‘no text-book yet produced is fit to succeed Euclid in the position of authority, and that a syllabus of propositions in a definite sequence to be regarded as a standard sequence for examination purposes, might be published.’ Such a syllabus as is here implied has been brought out by the Association for the improvement of geometrical teaching; and the committee recommend it for adoption by the universities and other great examining bodies of the United Kingdom. ‘It may be well to observe,’ they say in their Report, ‘that the adoption of this or some such standard syllabus would not necessitate the abandonment of the Elements of Euclid as a text-book by such teachers as still preferred it to any other, as it would at the utmost involve only such supplementary teaching as is contained in the notes appended to many of the editions of Euclid now in use; while it would greatly relieve that large and increasing body of teachers who demand greater freedom in the treatment of geometry than under existing conditions they can venture to adopt.’

Supplementary to our recent notices of the telephone, the following remarks, translated from a late number of the Telegraph Bulletin of the Ottoman administration, and dealing with a question of some importance to telegraph manipulators throughout the world, may be read with interest:

‘Is the telephone, yes or no, destined to replace other telegraph instruments; and seeing the possibility that people may use it without special training, is it in the end destined to destroy the career of telegraph employés? Those questions merit from us the labour of being examined with care. We think that that instrument will never be able to be employed in telegraphic working destined to serve governments and the public. In effect, supposing the instrument perfect, arrived at the last limits of perfection, and able to work at all distances with or without relays, then‒1. To transmit a message with all the advantages offered by the system, it would be necessary that the sender should be able to speak himself directly with the receiver, without the intervention of an employé. Now, all those who know the organisation of the lines know that this is not possible, that there must necessarily be intermediary offices of deposit, that the public cannot be admitted to the offices where messages are transmitted or received, and consequently the sender must give his message written. 2. An employé once charged with the message, the instrument has already lost one of its principal advantages, for that employé must read the message, and pronounce it to his correspondent; but if the message is written in a foreign language, the impracticability is evident. Lastly, the telegraph administrations now possess instruments which permit them to send messages with much greater speed than can be attained in sending them by the voice. Those reasons alone, and there are many others, ought then to assure the employés that this new invention will not put in peril their means of existence.

‘This is not to say that the telephone will not be utilised. On the contrary, it will probably be much used, but in special cases and for private use. For example: To put any chief in immediate relation with his employés in offices or manufactories; for the police of towns for announcing fires; for service of mines; to replace with advantage electric bells in many cases; and in a crowd of circumstances not yet foreseen. Let us wish then good success to this invention, which does honour to the era of steam and electricity.’