THE MONTH: SCIENCE AND ARTS.

'On the Transport of Solid and Liquid Particles in Sewer Gases,' is the title of a short paper by Dr Frankland, read at a meeting of the Royal Society. That particles of many kinds are constantly floating in the atmosphere, even at great heights, is well known. At times noxious or deadly particles are diffused among the mass, and disease and death are the consequence. Dr Frankland has proved by experiment that noxious particles can be conveyed long distances, and he sums up his conclusions thus: '1. The moderate agitation of a liquid does not cause the suspension of liquid particles capable of transport by the circumambient air, and therefore the flow of fresh sewage through a properly constructed sewer is not likely to be attended by the suspension of zymotic matters in the air of the sewer. 2. The breaking of minute gas bubbles on the surface of a liquid is a potent cause of the suspension of transportable liquid particles in the surrounding air; and therefore when, through the stagnation of sewage, putrefaction sets in, and causes the generation of gases, the suspension of zymotic matters in the air of the sewer is extremely likely to occur. 3. It is therefore of the greatest importance to the health of towns, villages, and even isolated houses, that foul liquids should pass freely and quickly through sewers and drain-pipes, so as to complete their discharge from the sewerage system before putrefaction sets in.'

The Birmingham Corporation sewage-works comprise a farm of two hundred and sixty-six acres in the valley of the Tame. The outflow of the two main sewers is treated with lime, which throws down the solid matters; and after the sewage has crossed a few tanks, the liquid portion flows into the Tame in a condition much less impure than the water of the river itself. The deposited sludge amounts to nearly four hundred tons a day. Great part of this is utilised by 'double-digging' of it into the land, three years being required to dig the whole farm. Another part is converted into Roman cement by General Scott's process.

The results appear to be satisfactory, for we are informed that 'the rye-grass grown on the farm averages from thirteen to fourteen tons an acre at each cutting, and several cuttings are obtained each year. After each cutting the land is immediately irrigated thoroughly with sewage, and in about three weeks the next crop is generally ready for cutting.'

At Manchester the Health Committee collect the excrementitious matters and other house-refuse in properly constructed vans, which are cleansed after each journey to the yard in the outskirts. There the whole mass is sorted; and what that sorting involves may be judged of from the fact that the quantity collected each week amounts to about three thousand tons, comprising 'paper, one ton; rags, three tons; dead dogs, cats, rats, guinea-pigs, and other animals, two tons; stable manure, seventeen tons; meat tins and old tin and iron, thirty-three tons; refuse from slaughter-houses and fish-shops, sixty tons; broken pots, bottles, and glasses, eighty tons; vegetable refuse, door-mats, table-covers, floor-cloths, and old straw mattresses, one hundred tons; fine ashes, one thousand two hundred and thirty tons; cinders, one thousand four hundred tons.'

In a communication to the Scientific and Mechanical Society of Manchester, from the Proceedings of which these particulars are taken, it is further stated that 'not only is patent manure produced, but disinfecting powder, mortar, fuel, and other useful commodities, all from the vilest refuse; and another matter for wonder is that all this abominable stuff is worked up with so little offensive smell arising from it. In addition to these works, there are workshops in which the Corporation make their own vans, pails, harness, and other requisite appliances for dealing with the new system of treating town-refuse.' No coal is bought: the cinders brought in furnish fuel enough for all the furnaces and heating apparatus, and for the 'destructors,' in which the absolute refuse which was formerly piled in huge heaps in different parts of the city, is burnt into harmlessness, while the heat is communicated to a neighbouring 'concretor.' 'The spent fuel,' we are told, 'is carted to the mills, and is there converted into mortar, a mortar too of the best description, as the samples of brickwork built with it abundantly testify.' Some of the most offensive refuse is passed through the 'carbonisers,' and 'is resolved into a perfectly harmless material.' From all this we learn that the art of keeping a town thoroughly clean may be made to occupy a high place among the useful arts.

The manufacture of iodine by distillation of seaweed, established a few years ago in the isle of Tyree and other parts of the West Highlands, still goes on, and as is stated, with tenfold increase. The selling price, which used to be 1s. 3d. per ounce, is now not more than 5¾d.

In America it has been discovered that the canker-worm, which infests fruit-trees to a mischievous extent, can be effectually checked and destroyed by smearing the stem and branches with printers' ink. It is interesting to know that there are two ways in which printers' ink can be made use of for the suppression of pests. And in France experience has proved that the Phylloxera can be destroyed by planting red maize between the rows of vines. The insects quit the vines and attack the maize-roots.

Meteorologists are well aware of the fact, that as a rule the barometer rises and falls twice within the twenty-four hours. Wherever observations are made, this movement is seen; and attempts have been made to refer it to the influence of tides in the air. But what causes the aërial tides? Some observers say magnetism, others say heat and differences of temperature. Mr Blanford, meteorological reporter to the government of India, has studied the subject; and in a communication to the Asiatic Society of Bengal, he remarks: 'It appears in a high degree probable that a great part of the diurnal irregularity of the barometric tides is due to the transfer of air from land to sea, and vice versâ, and to a similar transfer which may be proved to take place between the plains and the mountains. But the phenomenon is very complex, and much study and labour are yet required to unravel its elements, consisting as they do partly of elastic and reactionary pressure, partly of dynamic pressure, and partly of variations in the static pressure of the atmosphere. Till this shall have been done, and it shall be found, after all, that heat and its effects are insufficient to explain the phenomenon, it seems premature to resort to magnetic and electrical phenomena for the explanation of the barometric tides.'

Amateur meteorologists would do well to remember that the trustworthiness of the anemometer as a measurer of the force of the wind is seriously affected by the presence of trees; even a single tree will exert a disturbing influence. For wind-observations, the more open the space the better. We hear that the Meteorological Office is about to place at a high elevation an anemometer which will indicate its work to the observer below by telegraph. In the study of the weather, it would often be of advantage to know the rate and force of the wind on the top of St Paul's or Ben Lomond.

It had been noticed that ozone was developed by the spray of water when under pressure; Signor Bellucci was thereby induced to make observations at the Falls of Terni 'to ascertain if ozone was produced by the natural pulverisation of the water, especially as he had often noticed there the characteristic odour of ozone.' The tests employed completely demonstrated the presence of ozone, and that the quantity varied with the volume of water rushing over the Falls. From this result Signor Bellucci concludes that wherever water is converted into powder or spray, whether by a cascade, a torrent, or by the rolling of waves, there ozone is produced. 'It is noteworthy that the air over the surface of the ocean is richer in ozone than that collected on land. Hence the production of ozone may be due to the electrical state induced by the friction of the minute drops of water against one another, which is increased by the mineral matter suspended or even dissolved in the water.'

Land flooded by the sea generally remains barren many years. The Journal of the Chemical Society gives a German chemist's explanation of the reason why. The land is charged with too large a proportion of chlorine salts; it has a tendency to remain damp; and there is a formation of ferrous sulphate, which, as is known, exerts a very prejudicial influence on plant-growth. Land when brought into this condition by an inflow of the sea, should be drained as quickly as possible, and sown with grass or clover and allowed to rest. Experience shews that it recovers its fertility sooner if treated in this way, than when cultivated all the year round as arable land.

In the course of a lecture on the Motion of Waves in Air and Water, by Professor Guthrie, a light, hollow india-rubber ball was floated on water, and a vibrating tuning-fork was held near it. The ball moved towards and followed the fork. Why? Some people might say that the fork attracted the ball; but the lecturer decided that attraction had nothing to do with it. Each oscillation of a wave is followed by a reflection: in this case, the reflection pushed the farther side of the ball; from which the conclusion was drawn 'that there is no such thing as attraction—that the apparent pull will be found to be a push from the opposite direction. The approach,' said Professor Guthrie, 'need not necessarily be called attraction, and it is better in all cases to substitute the word approach, which is a fact, for attraction, which is a theory.'

Mr Siemens' paper on the Bathometer, which we noticed some months ago, is now published in the Philosophical Transactions. Objections have been made to the instrument as an indicator of the depth of the sea, because the sea-level is disturbed by the attraction of large masses of land. Mr Siemens answers that he is aware of the objection; that the bathometer is not expected to do more than indicate comparatively small variations in total terrestrial attraction, which the hydrographer or navigator using the instrument will have to interpret according to the circumstances of the case. If the zero-point of the instrument varies with the latitude, or in consequence of special geological causes, we must bear in mind that these causes are of a permanent character, and that when an ocean has been once surveyed by means of the bathometer, the special local conditions become observed facts, and would thus serve to increase the value of the bathometer as an instrument for measuring the depth of the sea without the use of the sounding-line.

At a meeting held at Salem, Massachusetts, a lecture on 'Visible Speech' was delivered by Professor Graham Bell, who, by means of the drum in a human ear cut from a dead subject, has succeeded in producing a phonautograph. The ear is placed in the end of an ordinary speaking-trumpet; on speaking into the trumpet the drum is set in motion; this moves the style; the style traces the effect on a plate of smoked glass; and by means of a camera the curves and lines can be exhibited to a large number of spectators. The five vowels make five different curves; and according to Mr Bell, there is no such thing as a sound or tone pure and simple, but each is a composite of a number of tones; and the wavelets by which these are produced can also be shewn on a screen. Tables of the various symbols have been drawn up, and found useful for educational purposes, as was demonstrated by a young deaf and dumb pupil from the Boston Institution, who interpreted the symbols at sight.

Professor Bell has improved the method devised by his father, formerly of University College, London, for rendering speech visible; and as is well known, membranes have long been used for experiments in acoustics. Some of our readers may remember the experiments of Mr W. H. Barlow, F.R.S., described in his paper 'On the Pneumatic Action which accompanies the Articulation of the Human Voice,' read two years ago at the Royal Society, and published in vol. 22 of their Proceedings. And within the past few weeks we learn that the telephone has been so far improved that an account of a public meeting was talked into one end of a wire and was distinctly heard and understood at a distance of eighteen miles.

There is good news for eaters of fish, for the government of Newfoundland have recently ascertained from the survey made by Professor Hind, under their authority, that the fishing-grounds off the coast of Labrador cover an area of more than seven thousand geographical square miles; about a thousand more than the Newfoundland fisheries. And there is good prospect of duration, for the Arctic drift brings down infinite quantities of the infusorial animals on which the cod-fish delight to feed. Owing to the higher latitude, the fishing season varies from that of Newfoundland; and it is found that the cod approach the shore one week later for every degree of latitude, going northwards. The coast of Labrador is described as similar to that of Norway, bare and rocky, and cut by fiords, some of which penetrate seventy miles inland. A summer cruise along that coast would be an interesting adventure for some of our yachtsmen.

The Smithsonian Institution at Washington does not confine itself exclusively to science, but makes itself useful in other ways. One of these ways is fish-culture; and we find from a recent Report, that in three years 1873-75, the Institution distributed forty millions of fish. Among these, shad and two kinds of salmon were the most numerous. The distribution is carried on under the superintendence of Professor Baird, an American naturalist of high repute.

A recently published part of the Royal Asiatic Society's Journal contains a report of a meeting held some months ago in which Sir H. Rawlinson stated that from the further investigations that had taken place there was reason to believe 'that the Hittites were really the chief people intervening between Egypt and Assyria, and that to them we owe the intercommunication of the art of those two countries.'

At the same meeting, Professor Monier Williams, in giving an account of his visit to India, mentioned that while there he had heard the learned men speak Sanscrit with astonishing fluency; and that in his opinion the day is approaching when Sanscrit will be as much studied in England as Greek.

One of the English delegates who took part in the International Statistical Congress held last September at Buda-Pesth, remarks on the disadvantage under which the Hungarians lie in their isolation from other nations by their language. It is a serious obstacle to their development; and as antipathies of race prevent their adoption of German, he recommends that they should take to English. In this he says: 'There would be no race difficulties, and the use of English would aid the Hungarians in more ways than one, and secure for them a predominance on the Lower Danube.'

If the present enthusiasm for African travel should continue, Africa will, before many years are over, cease to be an unknown country. Travellers from Germany, France, Belgium, Italy, and Portugal, are either actually at work or about to commence their explorations, in addition to the Englishmen who are always pushing their way into the interior. And now that Colonel Gordon (Gordon Pasha) has been appointed by the Khedive of Egypt governor of Sudan, facilities for travel in the equatorial regions may be looked for, and Æthiopia will cease to be a mystery.

We are informed that the use of leather belts for transmission of power in factories is more widely spread in the manufacturing districts than is implied in our paragraph on that subject (ante, p. 63), and that in the Anchor Thread Works at Paisley, where the belts were adopted four years ago, two thousand five hundred horse-power are transmitted by means thereof.

We take this opportunity of correcting an error in our recent article on Austrian Arctic Discovery. Lieutenant Payer's farthest point north ought to have been 82° 5′ instead of 85° 5′.

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