Professor Janssen, the well-known astronomer of Meudon Observatory,
who has done more than any man living, perhaps, towards wedding the
photographic camera with the telescope, has lately published some
account of a marvellous picture which he obtained of ‘the old moon
in the new moon’s arms.’ At the time that the picture was taken, the
moon was only three days old, and an uncovering of the lens for one
minute only was sufficient to secure the image. This image is feeble,
but is full of detail, plainly showing the general configuration of
the lunar surface. Professor Janssen believes that this application of
photography points to a means of obtaining more precise measurements
of the light, and of studying the phenomena which are produced by
the double reflection of the solar light between our earth and
its satellite. To the uninitiated, in these days of marvellous
instantaneous pictures, an exposure of one minute may seem rather
a long period. But let us consider for a moment what a very small
proportion of the sun’s glory is reflected to us from the moon, even
on the finest nights. Professor Sir W. Thomson gives some interesting
information on this point. Comparing the full moon to a standard
candle, he tells us that the light it affords is equal to that given
by such a candle at a distance of seven feet and a half. As in the
above-mentioned photograph the light dealt with came from a moon not
full, but only three days old, it will be seen that Professor Janssen
had a very small amount of illumination for his picture, and the only
wonder is that he was able to obtain any result at all.
It will be remembered that in the autumn of 1882, a series of
observations were commenced in the polar regions, which had been
organised by an International Polar Committee. Fourteen expeditions
from various countries took up positions in that inhospitable area,
with the intention of carrying out observations for twelve months,
from which it was hoped that valuable knowledge would be gained. This
programme has been successfully carried out, ten of the expeditions
having returned home, many of them laden with rich stores of
observations. Three remain to continue their work for another year.
As to the return of the remaining band of observers—belonging to the
United States—there is as yet no definite information.
On Ailsa Craig, Firth of Clyde, there is being erected, by order of the
Commissioners of Northern Lights, a mineral-oil gas-work, to supply
gas for the lighthouse in course of construction there, as well as to
feed the gas-engines which will be used to drive the fog-signalling
apparatus. The works are being erected by the patentee of this
gas-system, Mr James Keith, and will cost three thousand pounds. They
will be capable of manufacturing two thousand cubic feet of oil-gas
per hour, of fifty-candle illuminating standard. It has long been the
opinion of many that the electric light is not the best illuminant for
lighthouse purposes, and this installation at Ailsa Craig, following
one on the same principle at the Isle of Man not long ago, would seem
to indicate that the authorities think so too.
North-east of Afghanistan there lies a piece of country called
Kafiristan, which, until April last, had never been traversed by the
foot of a European. In that month, however, Mr W. W. M‘Nair, of the
Indian medical service, crossed the British frontier, and travelled
through the little-known region for two months. An interesting account
of his wanderings formed the subject of a paper read by him at a recent
meeting of the Royal Geographical Society. The country is inhabited
by three main tribes—Ramgals, Vaigals, and Bashgals, answering to the
three chief valleys, and each having a distinctive dialect. The men
are warlike and brave, but, like many other semi-barbarous peoples,
leave the heavy work of agriculture to the women. The Mohammedans hem
them in on all sides; but as the tribes are at peace among themselves,
they are able to hold their own. Slavery exists to some extent. The
people acknowledge one supreme being, Imbra, and worship at temples
presided over by priests; but to neither priests nor idols is excessive
reverence paid. Bows and arrows form their chief arms; and although a
few matchlocks have found their way into the country from Cabul, no
attempt has been made to imitate them. Wealth is reckoned by heads
of cattle; the staple food is wheat; and the favourite drink pure
grape-juice, not rendered intoxicating by fermentation or distillation.
Although there is every reason to believe that cruelty to animals is
far less common than it was, still there are many men who are not so
merciful to their beasts as they might be. Many of these offend from
ignorance, and will leave poor creatures exposed to inclement weather
under the belief that they will not suffer. Professor Shelton, of
the Kansas State Agricultural College, has lately shown, by careful
experiment, that it _pays_ to be merciful in the matter of providing
shelter for pigs; and we have no doubt that if his researches had been
extended to other animals, a similar result would have been obtained.
For this experiment, ten pigs, as nearly as possible alike with regard
to breed, age, &c., were chosen, five being kept in a barn, and five in
the open, but provided with straw to lie upon. These two families were
fed twice a day with carefully weighed messes of Indian corn. In the
sequel, it was found that each bushel of corn produced in the barn-fed
pigs ten and three-tenths pounds of pork, whilst each bushel given to
the outsiders formed only nine and seven-tenths. This result of course
clearly shows that a large proportion of the food given went to keep
the outdoor pigs warm, instead of adding to their flesh. If the bucolic
mind will only grasp this fact, we feel sure that more attention will
be given to the question of shelter for animals.
Professor Cohn, writing from Breslau to _Nature_, calls attention to
the circumstance that just two hundred years ago there was made in the
Netherlands a scientific discovery of the greatest importance. In the
year 1683, Leeuwenhoek gave notice to our Royal Society that by the
aid of his microscope he had detected in the white substance adhering
to his teeth ‘very little animals moving in a very lively fashion.’
‘These,’ says Professor Cohn, ‘_were the first bacteria which the human
eye ever saw_.’ The descriptions and drawings given by this first
observer are so correct, that even in these days, when the Germ theory
of disease has brought forward so many workers in the same field, armed
with much improved appliances, the organisms drawn by the hand of
Leeuwenhoek can be easily recognised and compared with their fellows
of to-day. These drawings have indeed never been surpassed till within
the last ten years, a fact which speaks volumes for their accuracy and
value.
The buildings occupied by the International Fisheries Exhibition at
South Kensington are, in 1884, to be devoted to a no less important
object, albeit it is not likely to be so popular with the masses. This
Exhibition will deal with matters relating to Health and Education.
It will include the food-resources of the world; the best means of
cooking that food; the costumes of the world, and their bearing upon
health; the sanitary construction of dwellings; and many other things
that every one ought to know about, but which very few study. With the
Prince of Wales as President, assisted by a Council including the names
of Sir Cunliffe Owen and Mr Birkbeck, the success of the scheme ought
to be assured.
In Cannon Street, London, an experimental section of roadway of a
novel kind has lately been laid down. It is the invention of Mr H.
F. Williams, an engineer of San Francisco, where the system has been
most successfully employed for the past seven years. Indeed, the roads
so prepared are said to be as good as when first laid down, allowing
for a reasonable amount of wear and tear. The process is as follows.
First of all is provided a good dry concrete foundation; upon this
are laid blocks of wood, grain-end uppermost, measuring eight inches
by four, with a thickness of an inch and a half. Each block, before
being placed in position, is dipped halfway into a boiling mixture of
asphalt and Trinidad bitumen; this glues the blocks to the foundation
and to one another, at the same time leaving a narrow space all round
the upper half of each piece of wood. This space is afterwards filled
in with boiling asphalt. Above all is spread a half-inch coating of
asphalt mixed with coarse grit, the object of which is to prevent that
dangerous slipperiness that is common to asphalt roadways in moist
states of the atmosphere.
At Brooklyn, the sanitary authorities seem to have a very sensible
method of dealing with milk-dealers in the matter of adulteration. They
invited the dealers to meet in the Common Council Chamber, when it was
explained to them by an expert how they could determine by various
tests whether the milk purchased from the farms is of the required
standard. At the conclusion of this conference, it was hinted that the
licenses of such dealers as were thenceforward detected in selling
adulterated milk would be peremptorily revoked.
At the end of December last, the first of four large silos on Lord
Tollemache’s estate in Cheshire was opened in the presence of a large
number of farmers and scientific agriculturists. It had been filled
with dry grass, chopped into inch-lengths by a chaff-cutter, and
pressed down with a weight equal to fifty-six pounds on the square
foot. The appearance of the ensilage was that of dark-brown moss,
having a pleasant aroma; but, as in other experiments of the kind,
the top layer was mouldy and spoiled. Lord Tollemache stated that he
found that animals did not seem to care for the fodder when first
offered them, but that they afterwards ate it with evident relish.
Several samples of ensilage were exhibited at the late Cattle-show
in London, and it is noteworthy that almost without exception the
pampered show-animals, when a handful was offered them by way of
experiment, took the food greedily. On Mr C. Mackenzie’s farm of
Portmore, in Peeblesshire, a silo was opened in December, the contents
of which—pressed down while in a moist condition—were found to be
excellently suited for feeding purposes.
It is worthy of notice that the past year brought with it the fiftieth
anniversary of the lucifer-match, which was first made in this kingdom
by John Walker of Stockton-on-Tees in 1833. The same year, a factory
was started at Vienna; and very soon works of a similar character
sprang up all over the world. In 1847, a most important improvement
was made in substituting the red amorphous phosphorus for the more
common variety. This modification put an end to that terrible disease,
phosphorus necrosis, which attacked the unfortunate matchmakers. The
strong agitation which this disease gave rise to against the employment
of phosphorus, naturally directed the attention of experimenters
to other means of striking a light; and although phosphorus in its
harmless amorphous form still holds its own, it is probable that its
presence in lucifer-matches will some day be dispensed with. We need
hardly remind our readers that the universal adoption of the electric
light would greatly curtail the use of matches, for that form of
illumination does not require an initial spark to set it aglow.
Some artillery officers in Switzerland have been putting their
snow-clad mountain flanks to a curious experimental use, for they have
been employing one of them as a gigantic target for their missiles.
A space on this snow-covered ground measuring two hundred and thirty
feet by ninety-eight feet—which would represent the area occupied by
a battalion of infantry in double column—was carefully marked out,
its centre being occupied by flags. At a distance of about a mile,
the artillery opened fire upon this mapped-out space until they had
expended three hundred shots. The ground was then examined; and the
pits in the snow when counted showed that seventy-eight per cent. of
the shots had entered the inclosure. Had a veritable battalion occupied
the ground, there would have been few, if any survivors.
In another experiment, snow was employed as a means of defence against
artillery. A wall sixteen and a half feet long, and five feet high,
was built of snow having various thicknesses, but backed by half-inch
wooden planking. This wall was divided into three sections, having
a thickness respectively of four and a half feet, three feet, and
twenty inches. Against the thickest section, twelve shots were fired
from various distances; but in no case was penetration effected.
In the three-foot section, shots pierced the snow as far as the
woodwork, where they were stopped. In the twenty-inch section, all
the shots fired went completely through the wall. It would seem from
these experiments that snow, when available, can be made a valuable
means of defence. But, unfortunately, in the published account of the
experiments, the calibre of the guns employed is not given; we should,
however, assume them to be field-artillery of a very light type.
A new use for the ubiquitous dynamo-electric machine is reported from
Saxony, and one which seems to fulfil a most useful purpose—namely, the
ventilation of mines. At the Carola pits, Messrs Siemens and Halske,
the German electricians, have inaugurated this new system. At the pit
bank, a dynamo is stationed, which is coupled up by shafting with the
engine. By means of copper conductors, this machine is connected with
another dynamo, two thousand five hundred feet away in the depths of
the mine. This latter is connected with a powerful centrifugal fan. The
cost of working these combined machines is six shillings and threepence
per day, which means threepence for every million cubic feet of air
delivered.
A new employment for the electric light has been found in Bavaria,
where a Committee has reported upon its use as a head-light for
locomotive engines. The colour and form of signals can be distinguished
by the engine-driver on a cloudy night at a distance of eight hundred
feet. The light burns steadily, and is not affected by the motion of
the engine; but a special form of arc-lamp is employed, the invention
of H. Sedlaczek of Vienna. The lamp is so constructed that it moves
automatically when the engine traverses a curve, so as to light the
track far in advance. The dynamo is placed just behind the funnel, and
is easily connected with the moving parts of the machinery by suitable
gearing.
The new patent law which came into operation on the first of January
will without doubt give a great impetus to invention in this country,
for many a man too poor to think of employing a patent agent, and
paying down nearly ten pounds for a few months’ protection, as he had
to do under the old conditions, can easily afford the one pound which
is now the sum fixed for the initial fee. Moreover, a would-be patentee
can obtain all necessary forms at the nearest post-office, and can send
in his specification through the same medium, without the intervention
of the ‘middle-man.’ Of course the law cannot be perfect enough to
please every one, and a few months’ practice will probably discover
many points in which it can be improved. One curious provision has put
certain manufacturers in a quandary, for it rules that no article must
bear the word ‘patent’ unless it is really the subject of a patent
specification.
A powerful antiseptic and deodoriser can be made by mixing together
carbolic acid and chloride of lime, which, when combined, contains
sufficiently active properties to correct fermentation. A weak solution
is used as a dressing in some gangrenous affections, as it does not
cause irritation. The smell, if objected to, can be disguised by oil of
lavender.
Fruit may be preserved in a fresh condition for many months by placing
it in very fine sand sufficiently thick to cover it, after it has been
well washed and dried and then moistened with brandy. A wooden box is
the best receptacle to use, and it should be kept well covered and in a
warm place.
According to some French gardeners, vines and other fruit-trees
infested with ‘mealy-bug’ should have their bark brushed over with oil
in November when the leaves are all off, and again in the spring when
vegetation commences. This mode of treatment is usually very successful
when it is applied to young and vigorous trees.
At a recent meeting of the Edinburgh Field Naturalists’ Club, a paper
was communicated by Mr John Turnbull, Galashiels, locally known as a
clever microscopist, in which he explained a new and simple method of
obtaining beautiful impressions of the leaves of plants on paper. The
materials necessary to take these impressions cost almost nothing. A
piece of carbonised paper plays the principal part in the process; but
it is of importance to have the carbonised paper fresh, and it should
be kept in a damp place, for when the paper dries, the pictures that
may be printed from it are not so effective. The leaf or plant to be
copied is first of all carefully spread out over the carbonised paper
on a table, or, better still, a blotting-pad. Next take a piece of thin
tough paper and lay it on the leaf. Then, with the tips of the fingers,
rub over the thin paper so as to get the plant thoroughly inked.
This done, place the leaf on the paper on which the impression is to
be taken. A smooth printing-paper gives the clearest copy. The thin
paper is now laid on the plant as before, and the rubbing continued.
Of course, care must be taken to keep the plant in position, for if
it moves, the impression will be faulty. However, the matter is so
very simple that anybody should succeed. Impressions taken in this
way have all the delicacy of steel engravings and the faithfulness of
photographs. His discovery is likely to come into favour for decorative
purposes. The headings of letters on the margins of books might be very
tastefully adorned with truly artistic representations of plants. The
wood-engraver also will find it will serve his purpose as well as, if
not better than, photography. Specimens that have been copied by Mr
Turnbull’s system, when examined with the microscope, are found to be
perfect, even to the delicate hairs that are scarcely visible on the
plant to the naked eye.