SCIENCE NOTES.

New Zealand Times, Volume XXX, Issue 4351, 1 March 1875, Page 3

SCIENCE NOTES.

(from our own correspondent.) Paris, December 26. . If a fresh drop of-blood be examined with a magnifying glass it will be found to contain an innumerable number of atoms, fiat in shape, yellowish red in color, disseminated like fine dust in a liquid. These atoms are the globules of blood, and play an important part in health and life. The greater their - number the more vigorous ought to be the body, and since graduated glass tubes enable the number of these globules to be counted in ten minutes, doctors have thus at their command a capital means for judging a patient’s system. The number of these globules not on’y differs in the case of each person, but varies with inodes of life, kind of foodj and the general conditions of existence. The'iron found in the blood fluctuates just as the globules. JIM. Malassez and Picard have conducted experiments in relation to the globules of blood and the presence of iron. The number of globules has been found greater or less after meals, and according to the kind of food consumed ; as also after exercise and perspiration, more especially after the latter, and when drinking is avoided. This increase may be largely attributed to the concentration of the blood,

and the quantity of liquid expelled by perspiration, as the increase is also observable after warm bath. Delicate persons will be happy V to learn that residence near the sea-side or in '"’the country, as compared with a city, augments the number of these globules by one-sixth, which implies an increase of strength and a better action of the organs. The number of globules is greater in winter than in summer, but in any case care must be taken not to confound the momentary with the permanent increase of these globules. After an hour s transpiration the body can diminish by several pounds in weight. M. Picard found, that in the case of oxen and dogs, the quantity of iron in the blood depends on the health, and can, in many instances, be double, so widely does its presence vary, and that this quantity is in relation with respiration ; that is to say, the better the respiration, the more of iron there will be in the blood, because the latter absorbs more oxygen ; and the more robust will be the health, when the blood is rich both in iron and oxygen. Hitherto it 'was believed that the bl»od contained the largest quantity of iron, and then the muscles. The spleen has now been found to possess the most—four times the amount found in the blood ; the liver ranks next, but its quantity never exceeds that present in the blood. The spleen would thus appear to be a reservoir of iron, the latter being put into circulation under the action,, of the oxygenised blood. As in winter the air is. denser than in summer, and hence richer in oxygen, in default of good air, • the globules diminish, and consequently when patients are prescribed tonics in the form of preparation of iron, their effect is very alight in the absence of wholesome air. Italian tourists will be glad to learn that the railway intended to deposit them within ninety yards of the crater of Mount Vesuvius will soon be made. Prom Haples to the foot of the mountain the distance is fifteen miles, and will, ostensibly serve for conducting provisions and produce to the market. The ascent proper of the mountain comprises a distance of three-, quarters of a mile at least, and will be effected, by means of a traction-train,, a stationary engine hauling the carriages up the incline by means of a wire rope round a drum. The station will be under the lava, and in case of eruptions, which take place every four or five years, the molten lava will flow over the crater terminus. During the late exhibition of fine arts applied to industry, the visitor remarked on entering the building the “Mysterious Clock,” consisting chiefly of a glass dial very transparent, presenting no appearance of “works,” and suspended .by two wires m the air : these wires served no electric purpose, as mh'ht on the first impression be surmised. The astonishment was the greater, when it was perceived, that the hands, free but isolated on the glass to which they were affixed, could turn in every direction, balancing themselves in their orbit if stopped by an indiscreet finger, and when liberated, returning, not to the hour which it was, but to that which it ought to be, and continuing to regularly move, as if never obstructed ' The hands themselves contain and conceal the works, and by an ingeniotis system of unequal lovers, to disturb theequilibrium, the motion is obtained. The minute hand is the pendulum, and at its base Is a watch movement, which displaces aplatina weight around the circumference of its box. The minute-hand is then made to be the leader of tho hour-hand, by means of a wheel-work. If the hands be put back or forward thirty minutes” they will both .return fo their right position. However, if rapidly the minute-hand will resume its correct position ; but the hour-hand will not; ’ The principle is not new r but its application is original.- ' The ‘ clock must be wound up every day ; can be easily repaired, and is coming into very general use in public places of amusement, where it can be hung, almost in space, apparently by threads, and being transparent can-be placed in a conspicuous position without being*an.

Dr. Magnan, as medical officer of the chief lunatic asylum of Fails, has'conducted a series of experiments to test the effects of alcohol on the animal economy. , He administered cognac to dogs; the animals became excited, aftenvards stupid, dropping into an insensible, sleep; the body became cold, and the fund legs paralysed. To these effects—only ephemeral —succeed in the course of a fortnight, intense nervousness, fear, hallucination, and trembling; if the brandy bo; suppressed after a month’s dosing, the animal becomes stupefied and dies. Absinthe, a preparation , of alcohol and wormwood, produces convulsions and something like strychnine twitches of the body. In brandy drinking, hallucinations occur at the last stage; but in the case of absinthe, during the first, in addition to convulsions or epilepsy. Chronic intoxication is not to be confounded with occasional hard drinking ; in the former, madness or paralysis ivariabiy ensues. The medical statistics of the French army for 1872, are very interesting, and reveal an improved state of health as compared with former years. The number Of hospital admissions was 252 per 1000 ; in point' of sanitary superiority the engineers are first, the transport corps and hospital attendants last Nearly 94, per cent, of the soldiers are vaccinated, and only 253 cases of small-pox occurred in an effective army of 430,000; of these, 200. had been vaccinated.; there were 214 cases of insanity, 35 being officers, and there is no proof that the war, as generally was supposed, has led to any. increase of insanity. The deaths were on an average 9J per thousand less than during previous years ; there were-144 suicides, 12 being officers, and self-destruction is most common among the light infantry ; .75 shot themselves ; 41 adopted strangulation, and 19 selected drowning. Con-

sumption is the most fatal malady, affecting over 2 per thousand of the ■imW, and forming nearly 22 per cent, of the total deaths. Typhus fever comes next., Whatever; may be the differences of opinion as to the'contagious nature of phthisis, the French report attributes s the large increase in deaths from ronaumptinn among tho hospital attendants to contagion. There were 6 deaths from hydrophobia, .of which 3 took place in Algeria, thus constituting a phenomenon, as hydrophobia is almost unknown among Orientals. Pulmonary - con-, sumption,is on the increase in tho,French army, and more than 4A per thousand represents the annual number of men definitely,! discharged from the army from this cause. A machine, perhaps more ingenious than" practical, has been invented for recording the votes of deputies. Before each deputy is placed two buttons as in the system of electric bells, one communicating with a. box containing j blue balls, and the other one containing white balls, representing the yes and no ; by pressing a button, a ball is liberated, and rolls into; an urn ; now as the balls are of equal weight, it is only necessary to weigh the urn to ascertain the votes recorded ; on the other hand, the balls remaining in the boxes, when similarly .treated,- will record the abstentiouists’ and the absent.

The eucalyptus has proved a great success since it has been introduced into Southern France and Algeria ; its marvellously rapid growth is only equalled by its utility both as timber, a medicament, and a powerful sanitary agent in marshy districts. It is, in addition, very ornamental. ■lt is as a purifier of an atmosphere filled with malaria that its great importance is due ; its odor is very penetrating and recalls something of the laurel; either from the intensity of its perfume or its property of absorbing deleterious gases in lands where malaria finds a home, and which is so propitious to its growth, fever disappears. Its leaves and bark make such an excellent febrifuge that they are now prescribed by French doctors as an economical sucoadaueum for cinchona. The tree unfortunately cannot resist a continued low temperature of 41deg. Farh., hence why it has only succeeded on the shores of the Mediterranean. There is a beautiful avenue of these trees at the station of Nice, and several pretty clumps of them at Cannes. In Algeria its cultivation has made wonderful progress, and companies are being formed to plant the marshy districts of Cor-’ sica and Algeria with the eucalyptus. At three miles from the famous chapel of St. Paul, outside Home, the Trappists have at present luxurious plantations of this tree, and the experiment thus on the border of the lugubrious Homan Campagna is full of promise for the reclamation of that waste. M. Adunson, in his voyage through Tunis, has discovered in the plain of Thala a forest of gum acacias, twenty by eight miles in extent. The trees are about twenty-four feet high and twelve in circumference, and the gum freely exudes from the trunk and the branches. Steps are being taken to collect the gum for exportation, and the Arabs have in the meantime been prohibited from cutting down the trees for firewood, as well as to make charcoal for the preparation of gunpowder. Dr. Fonssagrieve’s work on the hygiene and salubrity of cities is very interesting. He shows that the more a city is populpus and attractive, the more it tends to draw towards it the inhabitants of the country districts. Cities having a rocky, base, are most salubrious, as preventing the absorption of water ; and on the other hand, a clay substratum is unhealthy for opposite reasons. Holland is situated twelve feet below the level of the sea, and its chief cities are built on piles ; the coldness of the climate there proves a safeguard to health, just as Venice, built in a lagoon, with 150 canals for streets, is protected from fever by its north-easterly winds and the daily ebb and flow of the tidff. The highest habitation on the globe is the convent of Thibet, some 16,500 feet in altitude. Latitude equal, cities are a few degrees warmer than tho country, the materials of the houses and streets having.the property of retaining heat. The heat generated by animal life in Paris is estimated as equal to the 78th part of what the.city receives during ten hours of sunshine ; vegetabie*life, on the contrary, absorbs heat, and gives off much water by transpiration. There ore 164 cities in the world with not. less habitants, and the total urban population of the globe is estimated, at fifty millions, or the 23th part of the world’s inhabitants. In Paris there are 147 people to the square acre, in London 46 ; and 32 and 8 tenants, respectively, per house. Upwards of v4ff per cent, of the site of Paris consists of open space, and if the Bois of Vincennes and Boulogne, just at the gates, be excluded, the arteries for -aeration would: be , about 25 per cent. 1 Paris has some 103,000 trees in the streets, acting as so many Vertical drains. In warm climates the streets are narrow and the houses low—so as to keep off the direct rays of the sun; in cold climates the streets 'are wide and the houses high. In Paris; the law compels the height of a house to be in proportion to the width of the street, and-the streets are: paved, as being cheaper to keep clean and in repair, as well as superior for traction. Macadam has been nearly banished, and- wood pavement has been relinquished, as in drowning the noise of vehicles it has, .produced innumerable asoidents. Asphaltum is excellent where the streets are level.; Paris consumes as much gas as the whole of iptance, exacting in its manufacture half a million tons of coal, being the thirtieth of the total of the production of the French coal mines. The daily consumption of water is 175 quarts per inhabitant, soon to be raised to 215. : For drinking purposes, rain water is excellent, provided it can be preserved in good water-tight tanks as at Venice. Well water is strongly ; condemned, as being the source; of fevers and dysentery, and the supply from artesian wells even is only good when the source is profound. The average of human life is a little longer in the country than in the town, and the death rate of London is a little less than that of Paris; but then the density of occupants per house is, as we have seen, 8 in the former city, and 32 ■in ±he latter. In every capital in the world, it has been established, that, fever and consumption are moat frequent,'as the quarters of the city are most densely populated, and the same truth has been established in hospitals—the greater the number of patients, the higher the death rate. M. , Kastner has succeeded in producing “ singing flames ” by burning purified coal gas, so as to obtain the hydrogen as free as possible; the “feather” flames, so idpg as they are kept separate in the same tube, will, generate a series of detonations corresponding to musical sounds. ■ ■ ■

’ Combo belongs to the mallow order of plants, and is common in Egypt and Syria, where its comestible fruit is much in request. Its fibre can be woven into tissue; and can be separated from the plant by crushing: the latter, and washing the mass in a running stream. No chemical agents are required, and the white paste thus ;resulting, has been manufactured'into excellent paper by Messrs. Bonia. Combo yields 66 per cent, of fibre for industrial purposes. The oil contained in the seed can be extracted for the manufacture of soaps. Inacloth-cloansingfactoryatPuteaux, outside Paris, a fire broke out, caused by the development of electricity in the rubbing of the stuffs which had been previously dipped in a benzine bath ; the sparks of electricity crackled as if they had emanated from an electrical machine. :

M. Claude Bernard’s recent experiments demonstrate the constant presence of sugar in the blood, and that sugar is produced In the organisation, disappears therein, and undergoes incessant mutations ; that arterial blood guards sensibly its quantity of sugar, which quantity is lessened as the blood circulates; .but the return of the fluid, as venous blood, ,to the right cavity of the heart, is richer in sugar than < the same blood found at the extremities of the body. Where then does the venous blood find its new supply of sugar on its return passage? In the liver. Under no circumstances, then, is sugar absent from the blood.

The subject of the transit, of Venus has been exhausted ; all that we have to do is to wait for tho result of the calculations to demonstrate the measurements. M. Camille Flammarion puts ns on our guard not to be over sanguine, the difficulties of the details be-

iiig ;so great and so 'numerous. If the “ contacts” between Venus aiid* the Sim are fixed for.less than five seconds, we shall, only have a repetition of what we already know ; if they lesult in one or two seconds, nearer, astronomers will have’ the reward they labored for, and deserve in any case. r