on; 3, enlarged section of same with opening A; 4, external view of 3, C being DETAILS.-1, Ventilating cap with cover removed; 2, the same with cover cover, and LL lugs to receive ribs; 5, part of ground-rope and peg; 6, lower end of pole H with metal plate E and stop G.

(then 2nd battalion 60th Rifles), at Kilkenny; | ventilation." The Commissioners again state. | butt be forced into the ground beyond those stops. and although the weather was not unusually "that to remove as far as practicable the evils of wet for Ireland, still a misty dew penetrated overcrowding tents, it appears indispensably neces the canvas, and rendered everything within the sary to improve their ventilation." With retent uncomfortably damp. During the winter spect to the sanitary condition of the "Hospital of 1854, when I was in the Crimea, the general Marquees." the Commissioners state that the complaint of the British army tents was, that they usual method of ventilation in 'marquees,' is by were neither waterproof nor ventilated, and I can opening or raising the side walls; but this method well remember the wet and puddled state of the can hardly be said to be sufficient, even in favourwindward half-ground portion of the interior of able weather, and still less is it when, from rain many of the tents, caused from the incessant beat. or high wind, the sides cannot be opened. Even ing of the rain and wind against the canvas, which in the fine weather, it was remarked that the air latter was so ill adapted to resist the combined under the roof of the marquee was hot and stagaction of the rain and wind, for a continuous nant (although the sides were open), because there period of sometimes 10 days. On the contrary, was no provision for its escape above." The the "Turkish circular conical tent" was dry, warm, Commissioners state that "the whole question of and waterproof, owing to its covering being of ventilation, as regards field hospitals, is one of double cotton canvas; besides, from its great width very great importance;" and with respect to the and comparative lowness, it withstood the fearful rapid recovery of the sick and wounded, they hurricane of the 14th of November, when nearly state that "well-ventilated field hospitals answer all the British and French tents were blown down. much better, than would be fulfilled by a much With reference to the deterioration of the tents larger amount of ill-ventilated cubic space." Confrom the effects of the variation in the weather, Isequently, "to well ventilate a field hospital is, in find, on reference to page 123 of the printed "Re- other words, to save transport." They pointedly port of the Sanitary Commission," which was de- remark, that "a permanent and independent means spatched to the seat of war in the East in 1855-56, of ventilation is particularly required at night, that in the month of May, 1855, the Commissioners when the doors and side hangings are closed." recommended the striking and removal of some In their concluding remarks, they state "that tents to a fresh surface, owing to the damp state the atmospheric impurities arising from overof the ground inside the tents. The commis- crowding and defective ventilation of tents and sioners were informed that "the supply of tents huts, were a frequent predisposing cause of zymotic was deficient, and that it was impossible to strike | disease." And that "as the neglect of the sanithe tents pointed out, as they were too much de tary condition of camps, tents, barracks, and hoscayed to admit of removal." No. 3. Defect:pitals has hitherto, in all countries, climates, and With respect to the very important subject of seasons, been the cause of the largest amount of loss defective ventilation, &c., of the present army in armies, the whole subject (closely connected as tents, I beg to bring to your notice the recorded it is with the physical efficiency of Her Majesty's opinions of several professional men. The late forces) demands in future a practical development, Dr. Robert Jackson, "Inspector-General of Army commensurate with its importance to the public Hospitals," states, that " There is great room for service." During the last three years and five improvement, in the manner ordinarily employed months of the Peninsular war, at the period when for covering troops from the inclemency of the the greatest activity prevailed, the mean strength weather, during a campaign." He recommends of the British army amounted to 61,511 men, and the use of a carpet of painted canvas to be laid the sick to 13,815, being 224 per cent. The mean on the ground, inside the tent; and by prevent-ratio of inefficiency from wounds did not exceed ing the ascent of moisture, generated by the 14 per cent. The average strength of the British raised temperature within the tent, from its occu- army in the Crimea, during the ten weeks interpation (more particularly by the immediate, or vening between the 5th May and the 14th July, near contact of the heated bodies of the men 1855, was 38,507 men. The total admissions into with the surface of the earth), would greatly tend hospital were 22,541, or 58 per cent. of the force; to lessen those evils (arising from the contamina- the per-centage of deaths from wounds (exclusive tions of the air) to which soldiers are subject, when of deaths in the field) was 20 per cent.; whereas crowded together in close or unventilated tents. 744 per cent. admitted into hospital, and 96 per The Doctor recommends "a tent with a light cent. of the total mortality from disease, roof," but acknowledges "that the application of originated from zymotic cases, such as fevers, &c. it is connected with trouble." He further states, that "a roof, similar to that of a marquee, is liable to be overturned by strong winds, and a tent with close walls is liable to be contaminated."

MAJOR RHODES' TENTS.

With the view of supplying a remedy for the several defects of the present army tents, I will now briefly describe some tents of my own invenI must again refer to that valuable" Report of tion, not that they, being my own, merit a greater the Sanitary Commission" in respect to the gene-attention, but that I believe the proposed imral want of ventilation of our army tents. They provements will materially add both to the health state "That the most obvious sanitary defect in the and comfort, in all countries and seasons, of tents was their want of ventilation.""It is usual dwellers in tents, and I further hope may render on a march for 12 to 15 men to sleep under a bell Tents and Tent Life" more acceptable. From tent. The cubic space for each soldier is 51 to 64 the exposed diagrams, you will perceive that I cubic feet, but the consequent evils from overhave applied my system to three forms of tents, crowding tents would be greatly mitigated by ventilation. The indispensable necessity of renewing is embodied. No. 1 represents the skeletons or in all of which the same principle of construction the interior atmosphere of the tent is indeed fully uncovered frames of my field and hospital tents, recognised, for there are a few small openings for from which you may easily comprehend the simthis purpose near the apex of the tent, but they plicity and strength of their construction. The are of two small a size to be of use." Again, frames are composed of stout ribs of ash, bamboo, or any other flexible material. When required to pitch the tent, the prepared double-twisted ground rope or band is hooked together, and laid to the full extent of its own circle on the ground; the butt-ends of the flexible ribs are then inserted within the loops or openings already made in the circular rope, and when the latter has been stretched out to the form required, the butt-end of each rib is forced into the ground; and to facilitate this operation, the extremity of the rib is provided with a metal shoe in the shape of a wedge. The butt is also provided with stops, so that the twisted rope or band, now circulating round the butt, cannot slip up the rib, nor can the

"We had occasion to examine the ventilation

during the outbreak of cholera in May, 1855, and were struck on entering the tents by the foulness of the atmosphere. This led to inquiry, and we found the men were perfectly aware of this defect, and complained of it themselves, especially in the mornings." "At the same date we found instances of sick being treated under bell tents, and in going into one of these, we saw pans of peat charcoal on the floor, and were told by the surgeon that, were it not for the use of charcoal for absorbing the emanations from the sick, the air of the tent would have been unbearable-a very sufficient proof of the great necessity for a better

To render the ground-rope more secure, a peg is
driven over it at the centre between each rib.
The top ends of the ribs (if detached from the
butts) are placed into sockets, which latter are
secured to the top ends of the butts; the ribs are
now gradually bent inwards, and then inserted
into the socket-holes of a head prepared for them.
The latter has a large hole through its centre, for
providing top ventilation to the tent. The canvas
covering of the tent is then drawn over the frame,
and when the outer ventilating head-piece covers
the inner one, the bottom part of the tent-cover-
ing is strapped to the ground-band, by the means
of straps fixed to the inside canvas of the tent,
near its base. The tent is thus complete; but to
add increased stability, eight short outside storm-
ropes, previously attached to the canvas, are
stretched out and pegged to the ground. To
further add to the firmness of the structure, the
outside valise or canvas bag, in which the whole
tent was rolled up, is divided into two parts, and
then buttoned to the inside of the lower part of
the canvas of the tent, on buttons prepared for
that purpose. On that part of the canvas which
lies on the ground, are placed the butt ends of the
arms, the knapsacks, and other articles usually
required by a soldier in the field; by this extra
weight being laid on the canvas ground curtain,
at the sides of the tent, all round its base, not
only greater stability is given to the tent, but,
what materially benefits the men in a sanitary
point of view is, that the usual ground currents
of air which enter at the bottom of the tent, do
not by the above means blow direct on the bodies
of the men, thereby obviating the necessity of
providing straw to place round the bottom of the
tent, which at present is absolutely necessary to
prevent the men from getting stiff necks: by this
simple arrangement, the purchase of straw usually
supplied for tents is obviated; and what must be
clearly perceived is, that fewer men are liable to
catch cold, consequently the hospitals would be
much less encumbered, and the army rendered
much more efficient. It is the prevention and
not the cure of such trivial complaints that should
be most attended to. When it is necessary to
light a small fire within the tent, the exterior
ventilating head can be uncovered, so that an
easy and free egress of the smoke, is obtained.
With respect to the saving of space, when ground
is an object, I can pitch five of my hospital-tents
on the same number of square yards of ground as
is required to pitch (including room for the tent-
ropes) one Government hospital-marquee-thus,
one of the latter requires about 340 square yards
of ground (or 20 paces by 19), whilst five of the
former only require about 215 square yards of
ground. The space necessary for one of my hospital-
tents is about 63 square yards, or about 7 paces
by 9. This, is a decided advantage, when but a
small space can be procured for the encampment of
troops. My field-tents can, if required, be pitched
within a few inches of each other, thereby also
occupying much less space than the circular coni-
cal government tents. The cube quantity of air
contained in my tents is as follows:-"Hospital
tent," 30 feet long, 15 feet wide, and 10 feet high,
is equal to 2,383 cube feet; or about 119 cubic
feet for each soldier, having 20 men in the tent:
or for 30 men, about 794 cubic feet each.
tent," 13 feet diameter and 8 feet high, is equal to
531 cubic feet; or, for 8 men in a tent, about 66
cubic feet each; and for 12 men, about 444 cubie
feet each. "Guard-tent," 9 feet diameter, and 5
feet in height, contains about 159 cubic feet. An
ordinary "single-poled circular conical tent,"
without any side walls, but occupying the same
space of ground, and of the same height and width
as my field tent, contains about 354 cubic feet of
air, thus allowing about 444 cubic feet for each
man, 8 men in the tent; and about 294 cubic feet
for each man, 12 men in the tent. I beg to state
that all my tents are perfectly ventilated, and
that the government tents are deficient in that
most important particular. The number of cubie
feet of air allowed to each soldier in many of the

"Field

The annexed engravings illustrate, in plan view and side elevation respectively, the new balance. a is the shelf; b, the beam; ccc, three small tubes; dd, tubes for mercury; sss, three scale pans; 7, glass plates to cover; h, hole in shelf; P, platinum rider; t, small table; and rr, copper

rests.

Our Weekly Gossip.

We learn that the secret system presses uneasily, as we anticipated, upon Sir William Armstrong, especially since the novelty of his invention has been called in question-openly by some, privately by many. This fact has, if we are rightly informed, inhe method of mounting is not inferior in sen- duced Sir William to proceed with his application for sitiveness to that of the best constructed instru- a patent in the usual way. His name will accordingly ments, and the limits of its sensitiveness are farbe found on page 210 of our last Number in the list from being reached in the specimen above deof those who have given notice of their intention to scribed. As an illustration of this assertion, the proceed with their applications for patents. It should be understood that any person may enter an opposifollowing rough experiment is adduced. The tion to the granting of Sir William's patent, on the writer constructed a balance, of which the beam ground of want of novelty, on or before the 11th of was a tube of thick glass 22 inches long, and one April. It is probable, however, that those who would inch in external diameter, and weighing alone be best able to prove it old, if it be old, will be least 13 lb. The scale pan was loaded with a weight likely to trouble Sir William with opposition. The of 1 lb. The compensation was then readily absence of opposition will by no means establish the effected with mercury to such accuracy that the novelty of his invention. translation of a platinum rider weighing oth gr. along the beam, over a space equal to 15th of the length of the arm, sufficed to change the preponderance in favour of the one arm or the other, according to the direction of its transference. This roughly formed balance therefore, which, exclusive of the scale pan, did not occupy two hours in construction and preparation for use, was sensitive to a weight of sth of a grain, or to voooooth part of the weight to be estimated, and about both part of the whole weight supported on the fulcrum.

NOTICES.

We are compelled to postpone until next week. Plato (On Iron Dwellings), S.B. (On the Atlantic Cable), Captain Norton (On Concussion Fuze), and articles on Fishing Tackle and Jobson's Apparatus for Crushing.

of physiognomy. The muscles of the face are set in action by electrical excitation, and the various changes produced are recorded by photography; so that M. Ducheune's chart is, in fact, an album of physiogno. mical photographs. The experimenter has naturally attached a nomenclature to his album; he calls the great frontal muscle the muscle of surprise, and says that its elevation indicates astonishment, attention, and surprise, and his may be studied conveniently at a theatre, at the moment of the rising of the curtain. The contrary action, ex ressive of reflection, is said to be caused by the depression of the brow caused by the action of the orbicular muscles in the eyelids; for this reason, the name given to this latter muscle is the muscle of reflection. The little muscle which prickers up the brow in the centre is named the muscle of pain. The pyramidal muscle which strides the roof of the nose is considered to indicate ferocity, and is called in the new physiognomical list the wicked muscle. The two zygomatic muscles are called the laughing and crying muscles; and so on throughThe number of the "Commissioners of Patents out. In order to ascertain the degree of influence able for 2d, will be of very great value to patentees and Journal" for Tuesday last, March 29, although purchas- exercised by the muscles on the countenance, each others. was put in action apparently when the face was in It contains a complete list of the specifica- repose, and to render the experiment more decided, tions of patents for inventions enrolled under the Old the subject acted upon in most cases was an old man Law (prior to October, 1852), with the prices at with a blank face partly paralysed. The museles which the printed specifications of the whole are were first made to contract one by one, and the republished. The list also includes all those old law sults tabulated as expressive or inexpressive; they were then made to contract in twos and threes, and the patents with which specifications were not enrolled, together with memoranda of all surrenders and dis-effects of these contractions are called concordant or specifications is a few pence, but some of them are so The average price each of the printed discordant, according as their simultaneous excite ment produces the effect of a single well-defined pas bulky as to cost several shillings; 10s. 4d. is the sion, or a mere grimace. One thing seems to be highest that strikes our eye on hastily glancing at the proved by these experiments, namely, that several list, but we remember having before seen one or two, physiognomical changes which were supposed to be if we mistake not, as high as 15e. The whole the result of the combined action of two or more number of these documents is 14,359. different muscles, are in reality produced by the contraction of one single muscle or pair of muscles alone. The experiments were made on one side only of the face, so that each photograph has an excited and a non-excited side. These two might not very inappro priately be called physiognomical positives and nega tives. This application of electricity and photography combined may be of great use to artists.

claimers.

Captain Blakeley, whose improvements in ordnance are well known to the scientific public, writes to us as follows:-"We have all heard of the great 13-inch wrought-iron cannon, the gift of the Mersey Steel Company to the nation, yet its merits have been little All Advertisements occupying less than half-a-column discussed in public, probably because it was a gift, and

TO ADVERTISERS.

are charged at the rate of 5d. per line for any number of nsertions less than 13; for 13 insertions, 4d. per line; and or 52 insertions, 3d. per line.

Each line consists of 10 words, the first line counting as two. Wood-cuts are charged at the same rate as type for the space occupied. Special Arrangements for larger or Serial Advertisements.

To ensure insertion, Advertisements must reach the Office by 5 o'clock on Thursday evening each week. None can be received after that time for the ensuing number.

THE demand for Mr. E. J. REED's paper-
ON THE MODIFICATIONS WHICH THE SHIPS OF THE ROYAL
NAVY HAVE UNDERGONE DURING THE PRESENT CEN-
TURY, IN RESPECT OF DIMENSIONS, FORM, MEANS OF
PROPULSION, AND POWER OF ATTACK AND DEFENCE,"
has been so great that the Journal of the Society of
Arts, the MECHANICS' MAGAZINE, and all other Scientific
Journals in which it appeared in December last, are now
out of print. The demand still continuing, it has
been deemed desirable to reprint it in a separate form.
Aa 8vo. edition of it, in large type, and on fine paper, has,
taerefore, been prepared, and may now be had at the Office
of this Magazine, price 1s.

ELECTRO-MAGNETISM.

TO THE EDITORS OF THE "MECHANICS' MAGAZINE."

GENTLEMEN,-In the MECHANICS' MAGAZINE of Friday last (No. 13), I have read with much interest the account of Mr. Haines' experiments with different cores, which eem to have been made with great accuracy; and I doubt not they will be equally interesting to not a few of your readers. With regard to the concluding part of his letter, ny first impression was, that by a suitable extension of the core the power of the coil might be increased, but on further reflection, I am convinced that by any addition to the core at one end we only condense or concentrate the magnetic polarity at the other, and, therefore, do not gain any augmentation in the total amount of magneto-inductive force exerted upon the primary coil, but probably rather diminution in consequence of the diffusion of part of the magnetism in that part of the elongated core which extends beyond the coil. If this be the case, the only advantage obtained is increased energy at one of the holes of a bar electro-magnet-an advantage which may evidently, in some circumstances, be turned to good account.

I observe a typographical error in Mr. Haines' letter, which it may be useful to point out, namely, the word taking, which ought to read tripling.

LIST OF NEW BOOKS.
Brown's Mercantile Navy List, 1859, 7s. 6d.
Cassell's Popular Natural History, illust., Part I., 6d.
Chevreul's Laws of Contrast of Colour, new edit., 58.
Crawley's (Capt.) Chess, its Theory and Practice, 2s. 6d.
Forbes's (J. D. Occasional Papers on the Theory of
Glaciers, 8vo, 10s. 6d.. cl.

Illustrations of Natural History, coloured, 4s. 6d.
Simcas's (Capt. F. C.) Leading Principles of Gunnery, 8vo,
24CH, cl.

a most generous one. The impression, however, has
become general that this gun is cracked in the inside
in consequence of firing. I myself fell into this error,
when I saw the fissure, and have since spoken and
written of the gun as having shown a want of suffi-
cient strength. This makes it my duty to do what I can
to remove the erroneous impression which exists, and I
shall, therefore, be grateful to you if you will allow
me to make known through your columns that I have
discovered that the small fissures in the inside of the
barrel of this magnificent gun have not been either
caused or sensibly increased by firing, but were found
when it was bored, and were pointed out to the officer
of artillery sent to receive it."

Aluminium could heretofore be cast, moulded,
forged, and chased like other metals, but there was a
difficulty, or, at any rate, great inconvenience, in
soldering it. This has confined the application of the
metal to such objects as could be produced in one
single piece, and, as all practical men know, this class
excluded a very large majority of articles not only of
ornament, but also of utility. A silver coffee pot, for
instance, often consists of from ten to twelve pieces;
the spout is made in two pieces soldered together, and
is then of course soldered on to the body; the cover
mostly consists of at least four or five pieces. The
shops of Paris are filled with small ornamental
The extraordinary piece of ordnance mentioned in articles generally struck up in one piece; and plates
the preceding paragraph by Captain Blakeley, will in of aluminium have been largely used in contrast with
a few days be permanently placed in its position to gold, and with ornamental and carved woods, in the
form part of the sea-defences of Portsmouth. Midway fabrication of small coffers and boxes, and in the
between Southsea Castle and the western auxiliary ornamentation of cabinet work. But the lightness of
battery a bed of concrete has been made in the the metal makes it peculiarly applicable for many
shingle seven feet in depth, and on this the gun, articles of utility, and therefore it has been an object
with its carriage, platform, and loading crane, will be of considerable interest to find an easy mode of
erected. The gun commands the entrance to the uniting several pieces together. M. Mourey, of
channel of Portsmouth harbour. The following are Paris, has given much attention to the subject, and,
the dimensions of the gun, as given in the Times: having succeeded in his object, he has thrown open
Length of gun-From breech loop to muzzle, 16ft. his discovery to the world by describing and experi
6in.; from base ring to muzzle, 13ft. 8in. Base ring menting upon it before the members of the Society
Circumference, 11ft. 4in.; diameter, 3ft. 7 in. for the Encouragement of National Industry. This
Muzzle-Circumference, 7ft. 14in.; diameter, 2ft. gentleman, having failed in all his attempts to solder
34in. Bore-diameter, 1ft. lin.; length, 13ft. 34in. aluminium as other metals are soldered by preparing
Thickness of metal at breech, 1ft. 10in., at vent, lft.
the two edges and at once uniting them by means of
3in.; at muzzle, 74in. Trunnions-Circumference,
a more fusible metal or alloy, was driven to various
3ft. 1 in.; diameter, lft.; length of shoulder, 11 in. experiments, and the following is the plan he now
Distance from centre of trunnions to base ring, oft. recommends:-He prepares each piece separately by
4in.; to muzzle, 8ft. 3 in. Circumference of gun covering its edge with a preliminary solder, composed
round the centre piece or band, 12ft. 9in.; weight of of aluminium and zinc, and he then unites the two
gun, 22 tons; weight of shot, 3 cwt.; service charge edges by means of another solder containing a larger
of powder, 781b. The carriage and platform were proportion of aluminium; and he thereby obtains a
manufactured at Woolwich of teak, and are bolted perfect joint. He prepares the edges with a mixture
together in the strongest possible manner. The of turpentine, balsam of copaiva, and lemon juice; the
carriage weighs 3 tons 2 cwt.; the weight of the plat-pieces are placed over hot charcoal, and a jet of flame

form is 4 tons.

"Electrical Physiognomy" is the only title we can find on the instant for a curious subject introduced a few days since to the members of the Club of the Scientific Press of Paris, by Dr. Mallet. A medical man named Ducheune, of Boulogne, has given much attention to curative electricity, and has thus been led to make a series of curious and important experiments by means of electrical currents on the duty of the various muscles of the human face, from a physiognomical point of view, and has produced a kind of chart illustrative of those functions for the use of those who take any interest in the study

is blown along the part to be soldered; the joint is then covered with morsels of an alloy composed of six parts aluminium and ninety-four parts zine; these being melted adhere to the surface and are pressed down by means of small tools made of aluminium. The difficulties of the operation are said to be not greater than in the case of hard soldering of copper, When the two parts to be united have been prepared as above described, they are held together in the usual and soldered by means of an alloy consisting of eighty parts of zinc and twenty parts of aluminium. The joints thus made may be worked or touched up as though they consisted of the unalloyed aluminium,

manner,

Mr. J. Downie, of North Woodside Ironworks, has read a paper to the Glasgow Philosophical Society on a new design for river steamers for passenger traffic. Mr. Downie proposes a sort of compromise between Yankee and British vessels-a steamer with the main deck lowered four feet from its present level, the side plates partly removed and replaced with strong plate glass, the side plates to be used in stiffening the hull, and a roof run the whole length fore and aft over the maindeck. A vote of thanks was given to Mr. Downie for his paper, but opinions were expressed that such a vessel as was proposed would scarcely be safe with an upper deck of the nature described, as there would be danger of an upset if the passengers ran to one side of the ship. Mr. Neilson thought that the objection might be removed by narrowing the upper deck. The new rifled Ordnance Department, in the course of organization in Woolwich Arsenal for manufacturing Sir W. Armstrong's guns, under the superintendence of Mr. J. Anderson, according to existing arrangements, will commence operations early in the month of May. Sir W. Armstrong, it is said, has expended upwards of 7,000l. on the initiatory experiments to test the efficiency of his invention.

Mr. F. A. Abel, the chemist to the War Department, has been making a series of experiments on the practising ground of the Royal Engineers at Brompton, Chatham, with an invention of his for firing charges of mines, blasts, &c, by magnetic agency, instead of by the old plan of fuses and slow matches. The experiments have been carried out in presence of a number of Royal Engineer officers of eminence now at head-quarters, all of whom have expressed themselves satisfied with the trials.

Dr. Lardner recommends a resort to destructive agents intended to operate not mechanically, like existing instruments of war, but chemically, for war purposes. Compounds are known, he says, in chemistry which, when exposed to the air, spontaneously ignite, diffusing through the surrounding atmosphere gases, or vapours, of odours so insufferable that men forced to respire them would be rendered utterly incapable of all effectual action. Shells charged with such compounds, exploding in the gunroom of a vessel, or anywhere between decks, would, without destroying life or limb, disable the enemy. There are others of a more formidable character. There are the "kakodyles," of which arsenic is one of the constituents, which on exploding not only diffuse exhalations which render the surrounding atmosphere so fetid as to be absolutely insufferable in respiration, but impart to it also qualities which are poisonous in the most deadly degree. These compounds being eminently volatile explode spontaneously when exposed to the air. In burning, the metallic arsenic, one of their constituents, combining with the oxygen of the air, forms fumes of white arsenic, which, being diffused through the surrounding air, kill all who breathe it. But the laboratory can furnish agents still more destructive. There are compounds into which the gas called cyanogen enters in combination with arsenic. A shell charged with such a compound upon exploding would produce terrific effects. By the explosion of such a shell the surrounding air would be instantly impregnated with the vapours of two of the most fearful poisons known in medicine. Before such agents, says the Doctor, gunpowder would "pale its ineffectual fires."

Messrs. Miller and Taplin have delivered an official report on the comparative merits of Newcastle and South Wales coals for steam purposes. They state the result of their experiments to be that the Welsh coal is 5.3 per cent. better than Newcastle in economy, but that the latter is 15 per cent. better than the former in regard to the rate of evaporation. On the whole, the advantages of the one description of coal over the other are scarcely appreciable, and the report recommends that another trial should be made in the Government Dockyards by Government officials without the presence of either interested party.

At the date of the last report of the chief inspector of the Manchester Association for the Prevention of Boiler Explosions, that society had 1,466 boilers under inspection. Of these 107 are found to be defective,

from causes classified as follows:-Corrosion 20, of which 6 were dangerous; fractures, 3; safety valves over-weighted and otherwise out of order, 31; pressure gauges out of order, 20; water gauges out of order, 17; feed apparatus out of order, 5; blow-off cocks out of order, 9, 1 dangerous; and deficiency of water, 2. Ten boilers are reported as without glass gauges; 28 without blow-off cocks; 3 without pressure gauges; and 7 safety valves had the spindles passed through stuffing boxes.

A body of workinen, 300 to 600 strong, are about to be set to work on the Crinan canal, on which a serious accident recently took place,

The death is announced at Edinburgh of Mrs. Tay-
lor, widow of the late Mr. James Taylor, whom Scottish
writers contend was the first to apply steam to the
propulsion of vessels, having launched a small steam-
boat on Dalswinton Loch in October, 1788.
One of Boydell's traction engines is now working
between Manchester and Little Hulton. Another
item of Manchester news is the appointment of Mr.
Joseph Baxendale as Corporation Astronomer," in
the room of the Rev. H. H. Jones, deceased.
Mr. W. T. Ansell has undertaken the management
of the Levant telegraphs.

The work of clearing the Nene of the dams placed in it by the Nene Valley Drainage Commissioners is being actively pushed on, but the complete removal of the piles of the Waldersea dam will not be effected for a week or two. The wings are cleared away, and an opening has been cut for the passage of the water, so that there is now no impediment to the drainage. The Wisbeach Corporation insist on the removal of every obstruction in the river to Peterborough.

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At a meeting held last week by the Hexham Farmers' Club, the cost of cutting an acre of an average crop of wheat (28 bushels) by the various methods of reaping was estimated as follows:-By sickle, 12s.; by scythe, 9s. 6d; by machine with side delivery in swathe, allowing the machine to cut 12 acres per day, 3s. 10d.; by machine with back delivery, allowing 9 acres per day, 3s. 9d. The decided comparative economy of reaping machines is too obvious to require comment. The Hexhamites expressed a preference for machines with back delivery.

the cylinders is lower than the other two, and when a light is applied to the holes the small blue flames issuing from them may either be kept separate or made to join in a large vertical flame. It is in the midst of this flame the test-tube is placed, resting on supports of wire which traverse the chimneys of the lamps. These chimneys are tubes bent in the form of an inverted U, and are equal in number to the lamps. The operator is not exposed to any inconvenient radiation of heat, since the chimneys, which are of sheet-iron, hardly receive any warmth during the experiment, which shows that nearly all the caloric has been absorbed by the test-tube.

Dr. Russell, the special correspondent of the Times in India, repeats in the most explicit manner his assertion that on an examination of the new Enfields at Allahabad, conducted by Lord, Clyde and Sir William Mansfield in person, with the assistance of military officers, a considerable variation in gauge and diameter was found in the barrels of the recently arrived muskets. "Captain Butt, of Her Majesty's 79th Highlanders, an excellent officer, skilled in musketry, found," he says, "by means of a gauge made for the purpose, that there were in the muskets of his company alone variations in diameter which would affect the loading. In fact, it is patent to every officer in the army who has been engaged in the war that at least 15 per cent. of the Enfields are ren dered useless after firing 10 or 12 rounds. It is quite possible that some proportion of the Enfields are injured by ill-made cartridges or unskilful loading, but the question of the existence of a variation in From the progress made on the Salisbury and the barrels is not at all affected by those accidents, Yeovil and Yeovil and Exeter lines, it is expected that as the difference has been ascertained by exthrough narrow guage communication will be esta-periment and by practical use in the field. A corblished between Exeter and London in the course of respondence has taken place on the subject, in which eighteen months. Colonel Dixon suggests that the barrels may have been injured by the men using violence to unfix their bayonets, and so compressing the tender substance of the iron tube, and then denies that there is any difference which can be appreciable in the field, or that any officer can detect it unless he be a profes sional viewer,' and a professional viewer,' I dare say, we shall have to set the question at rest, coming all the way from England to Allahabad to do it. It is desirable to dispose of the matter for the sake of the makers, and for that of the service. Why should not test gauges have been furnished to the arsenals here?"

A report of the Ordnance Survey and Topographical Depot to the end of the past year 1858, was published last week. It gives a detailed account of the progress of county, parish, and town plans and military surveys. The expense for the Ordnance surveys to be provided for in the current year's estimates is £90,000. The sale of ordnance maps last year realised the sum of £5,499, including those supplied to public-offices, &c.

In spite of the decision of the Committee of the Stock Exchange, the works on the Aidin-Smyrna Railway are continued with energy. The difficult cutting at the beginning of the line has been finished; and what remains now up to the tunnel is one uninterrupted plain, where scarcely any earthworks are required. At the tunnel itself the diagonal shaft on the Aidin side has been sunk to 50 fathoms, during the first 25 or 30 feet through solid limestone rock, after which a layer of clay was found, very easy to work, and yet of sufficient consistency not to require masonry. Thus, the most formidable part of the line promises to give far less trouble than was expected.

Mr. John Anderson, assistant engineer for rifled ordnance, has, it is said, taken charge of the old Lancaster shell foundry in Woolwich Arsenal to commence the manufacture of Sir W. Armstrong's guns, 48 experienced men employed in the Royal Standard gun foundry having been transferred to that department. Various other arrangements have likewise been entered into for proceeding with the manufacture of the new guns without delay.

A correspondent, after reading Mr. Forster's lec ture on aluminium, which appeared in a late number, has forwarded us a copy of a paper on Ammonioiodides of metals read by the Rev. J.B. Reade, F.R.S., at the British Association in 1857. After the reading of the paper, Dr. Lee said :-" I would also observe that with respect to the last metal alluded to in the paper, cular object in not putting the solution of iodine in viz., aluminium, Mr. Reade seems to have a parti direct contact with the pure metal, as in the other examples. Here he takes an oxide of the metal, alumina, and by a new process attempts to solve the problem which has so extensively occupied the atten tion of practical chemists in extracting the pure the great basin of Kimmeridge and Oxford clay in the metal from its compounds. Mr. Reade lives upon of a fortune, lying, however, under his feet, but which Vale of Aylesbury. He is, therefore, really the owner only requires the wand of the chemist to transform it into pure metal and current specie."

"An attempt is in progress on the part of the Great Western Railway Company which is likely," says the city article of the Times, "should it prove successful, to destroy the only protection enjoyed by the public against a constant increase of the evils of the monopoly conferred by Parliament on this and all similar undertakings. A private Bill has been introduced, in a covert form, to enable them at pleasure to raise their fares for passengers and goods to an extent ranging from 50 to 100 per cent., as well as to acquire other powers with the view, apparently, of screening their arrangements from observation. It is stated to have been merely by accident that the trading community discovered the project in time to take steps for its defeat. The Bill is entitled A Bill for authorizing the construction of a railway for carrying the West London Railway over the Great Western Rail. way, by means of a bridge in substitution for the present level crossing; for revising the tolls of the Great Western Railway Company, and for other purposes,' and it was in this manner, by putting forth MAP OF ENGLAND AND WALES.-An exceedingly the change of a crossing into a bridge as the promi- well executed map of England and Wales, mounted nent object, that it was hoped to gain the means to on canvas, coloured, varnished, and attached to a tax to an almost indefinite degree the entire traffic of the west of England. A more unworthy contri-roller, has been placed within the reach of every vance has perhaps hardly been recorded in the annals of a respectable English company."

Galignani gives us an account of an improved gasapparatus for heating test-tubes, and for other laboratory purposes, the invention of M. Bertholet. It consists of six lamps and as many chimneys, which may all be placed in any way the operator may require. Each lamp is composed of three horizontal iron cylinders 15 centimetres in length, and 24 centimetres in diameter. Each of these cylinders has eight rows of very small holes parallel to the axis, and others in its bases, besides a large one in one of them, into which the tube conveying the gas fits. One of

one who has 3s. 6d. to spend on so useful an ar ticle, by Messrs. Everett and Son, of Bouveriestreet, Fleet-street, London. This production deserves mention in our columns as a specimen of what the mechanical arts are doing in the way of educating the masses. The map has been most carefully reduced by Mr. J. Cooper, from the great Ordnance map of England and Wales, and the southern parts of Scotland; it has all the lighthouses, sands, and soundings round the coast accurately laid down, and showing all the railway and mail-packet communications,