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lbs., being a loss of 3413 lbs., or more than one-third in seasoning, Nearly all of this decrease took place within two years and a half. A remarkable fact is to be noted in this experiment, viz., that the wood again increased in weight when a rain even of two days occurred immediately before the monthly time of weighing. It may hence be assumed that damp or rainy weather may retard the seasoning of timber, and even cause it to retrograde.
The remains of the sap being conceived to operate against the durabili ty of timber, various processes have been devised to assist in removing the organic matter originally held in solution in the sap, and also to expedite if possible the seasoning. Barlow has a paragraph on the subject so much to the purpose that we give it entire.
"The process of seasoning may be facilitated by boiling, steaming, &c., as appears from the following experiments of Mr. Hookey. The three pieces marked Nos. 1, 2, and 3, were English oak, each four feet long, and three inches square; all cut from the same timber. No. 1 was placed in the steam kiln for twelve hours, No. 2 was boiled for the same time in fresh water, and No. 3 was left in its natural state. The weights of the three pieces, previous to the experiment, and at the end of each month for half a year afterwards, were as stated below.
"Each of the pieces was placed in the same place, in the open air, and in the same position, (i. e. vertically,) after the experiment, and were continued so during the six months that their weights were taken.
From the above, it appears that the process of seasoning went on more rapidly in the piece that was steamed than in that which was boiled; but that in the latter, the process was carried on much quicker than in the piece which was left in its natural state:
The first had its specific gravity reduced from 1050 to 744.
And the third
from 1084 to 788.
from 1080 to 928.
We must look to the philosopher for a satisfactory solution of the pro
blem presented in these results. Mr. Hookey accounts for the facts by supposing, that the process of boiling or steaming dissolvs the pithy substance contained in the air tubes, by which means the latter fluid circulates more freely, and that the seasoning thereby proceeds with greater rapidity."
But these are not the only means of facilitating the seasoning of timber. In a process for preserving timber which we have several times noticed, (and of which an advertisement may be seen on our cover,) the wood is subjected to such a heat as fills all the vessels with steam, and on its immersion into a cold solution of, a peculiar resinous compound, the steam is condensed and the antiseptic compound forced quite through the stick.
It is manifest, that by this, or any analogous process, the sap is deprived of all power of injuring the quality of the wood-while the greenest timber is immediately seasoned, for all moisture is expelled, and checking cannot take place, as the pores or vessels are instantly filled by the resinous matter which keeps them distended to near their former size. No shrinking or alteration of fibres need take place, and hence the whole object of seasoning" is answered without waiting "a season."
The importance of thus accomplishing two important objects by one operation and without loss of time, is not to be overlooked. In the construction of railroads in timber countries, an immense saving of money and time might be made at the same time that the durability of the structure is insured.
The following is one of many excellent papers in the Annals des ponts et chauesees which have never yet appeared in an English dress, and which we have translated for the benefit of our readers.
Although the article on breaking stone was published some time ago, it has not lost its value. In fact, an additional interest belongs to it, when considered in connection with the more common modes of constructing railroads-broken stone constituting no small portion of the material. It will be seen on refering to the Report of Camden and Amboy railroad company, that they have expended the enormous sum of $103,372 64 cents for broken stone. How much of this might have been saved by the substitution of mechanical for intelligent power, we do not pretend to say, but that some saving would result, is beyond all doubt.
We hope that American ingenuity will yet supply the desideratum so well delineated in this article.
ON BREAKING STONE.
Extract from an article by M. E. F. Noel, Ingenieur des ponts et chaussees. The breaking of materials intended for working stone roads, is a yearly work of considerable magnitude. Without being able to state precisely the bulk of stone broken annually in France, and applied simply to the working of the royal and department roads, I do not think it can be less
To this gentleman is due the ingenious idea of bending large ship timbers.-See Transactions of the Society of Arts, vol. xxxii.
than 4,000,000 cubic metres. To this amount is to be added that of the stone employed for roads in process of construction, an uncertain amount, but considerably augmenting the number of millions of cubic metres. The art of stone breaking is thus employed upon an immense mass of material, and becomes a matter of great importance. Nevertheless, the operation is carried on exclusively by manual labor, and in the most imperfect manner. It is well known that the blow is the most disadvantageous employment of power, and that in all kinds of machines, it is in portant to avoid all shocks on account of the loss of power which they occasion. Now, the breaking of stones is nothing but a repetition of frequent blows, and what is worthy of remark, the power which is thus lost in these multiplied blows, is the most valuable and the most dearly purchased-that of man. The imperfection of the operation is manifest, for it is very costly. English engineers have advised, and with propriety, to cause the breaking of stone to be done by women and children, seated, and furnished with a light hammer, having a short handle, this method is in fact preferable to breaking with heavy blows of a long handled sledge, used by a strong man, standing up. But it is only applicable when the materials are already reduced to a size not more than double that which is desired, for when they are larger, when, for example, rough stones from the quarry are to be used, breaking them by children, seated, is impracticable, and it will then be necessary to use a sledge, and to work it standing. In this case, there must be a double breaking. The first, to crack up the rough stone, and the second, done by children, seated, to reduce the stones thus broken, to the desired size, which should be such that each piece can be passed through a ring 06 of a metre (about 2-3 inches) in diameter.
Besides this mode of operating, by short hammers and seated workmen, although, in fact, far preferable, has to encounter pejudices very difficult to overcome, both in the contractors and in the workmen themselves, so that the use of the long sledge, worked by strong men, standing, and constantly bent over, is the plan most generally followed.
To the most striking inconvenience of this method, which consists in employing, at a dead loss, a large amount of intelligent power, must be added the difficulty of breaking the stones properly and uniformly-the scattering of the broken stone, which must be picked up-the loss of the detritus which is spread on the ground and cannot be collected-and also the opportunity which the workman has to defraud by neglecting the breaking of the centre of the heap.
Under these circumstances, it would be desirable to apply some mechanical means to the breaking of stones. It appears that there can be employ. ed for this purpose, a machine composed either of a core or spindle, furnished with projections, and turning upon its axis in the interior of a circular piece likewise furnished with projections*-or of two cylinders horizontally channelled or fluted, and turning towards each other, with a space left •Resembling a coffee or brick mill. (Ed.)
between them-or lastly, of a single moveable cylinder, revolving on its axis over a fixed parallel plane, and producing the crushing between itself and the plane. These instruments should be made of very hard steel, and in order to avoid their fracture, by reason of the hardness, or particular position of a stone, the pieces against which the strain is exerted, might be so arranged as not to be altogether rigid and fixed, and to give way before the strain when it approaches a certain limit.
Thus, for example, the circular piece, in the centre of which the spindle of the stone mill turns, instead of being fixed, might be made of three or four segments, susceptible of a movement from the centre, to let pass unbroken fragments offering too great resistance, when these pieces shall have exerted upon them a strain capable of moving the springs which keep them in their proper position.
A very strong fly wheel will also be necessary to assist the power, since this will have to overcome very variable resistances.
There must also be arranged between the breaking instrument and the recipient of the broken material, a suitable apparatus for sifting these materials, so as to separate the fragments of various sizes, from those which have passed through the machine without being broken down to the detritus or powder.
It is very probable, that a single instrument will not suffice, and that to obtain the size desired, there must be, when rough quarry stones are used, a series, more or less numerous, of this sort of tools.
The solution of this problem will render a great service, in point both of art and economy-and in this view it will be desirable that those engineers who have already made any experiments upon breaking stone by machinery, should give to the profession the results of their labors, through the medium of the Annales.
GREAT WESTERN RAILWAY IN UPPER CANADA;* EXTRAORDINARY ADVANTAGES OF THIS ROUTE TO THE CITY OF NEW YORK AND TO
SOME OF THE WESTERN STATES.-W. R. Casey, Civil Engineer. "The aim of this paper, is to place in their true light the objects and advantages of the Great Western Railway. It does not profess to embrace all the merits of the question, but it is an attempt to bring forward the more prominent and the very peculiar advantages offered by this route to the city of New York, and some of the most flourishing parts of the West. It does not dwell on the beneficial effect the road must have on the general prosperity of the Province-and especially on that part through which it will pass, for this is much better understood by the permanent residents of the country-but it investigates the claims of the Great West
The Great Western Railway is to run from Hamilton, at the western extremity of Lake Ontario to the river, or Lake St. Clair, its western terminus not having been decided on. The quoted passages and the substance of the remarks generally, are from an unpublished memoir written in 1837, in which year a copy was given to the Hon. John Hamilton of Queenstown, U. C.
ern railway to rank as an important link in the BEST chain of communication between the West and the waters of the St. Laurence and the Hud
These two rivers may be considered as the grand feeders of the Great Western railroad. By the former it will receive travellers and emigrants from both provinces, as well as from the northern parts of New York and of the Eastern States embarking on the St. Lawrence and on lake Ontario; by the latter, travellers and emigrants from all parts of the world, by the way of New York. Now, it is obvious, that the western railroad is the best possible route for the former, and it remains to be shown, that it offers the quickest, easiest, cheapest and earliest route to the country west of Sandusky for all travellers by the Hudson, whether they take the direct route across Ontario, or continue, on the New York railroads to the Falls.
A large proportion of the present population of the States of Ohio, Indiana, Illinois, Michigan and of the Territories still farther west is supplied with goods from the city of New York, to purchase which, the country merchants make annually one or more trips to that city. These form a very profitable class of passengers, paying the highest fare, and producing a fixed income. Although the agricultural products of the country will continue to go by Lake Erie, the merchants themselves will take that route to New York which requires the least time. The number of travellers between the north western part of Ohio, the northern part of Indiana, and of Illinois, the State of Michigan and the western Territories is well known to be very great and steadily increasing, in addition to which, crowds of emigrants must yet for centuries flock to the boundless west. It should be the object of the Great Western railroad to secure this business, which it can only do by offering superior advantages to travellers between the Atlantic and the mouth of the Maumee river and Detroit -the keys to the country west of Sandusky. As already observed, local business is omitted, not because its present importance and steady future increase are not appreciated, but, because it is believed, that the western travel alone exists, and may be commanded to an extent sufficient to ensure an immediate and handsome return for the capital invested in this undertaking."
It would appear at the first glance that the Great Western railway must contend, on something like equal terms, with the roads from Boston, New York and Philadelphia, striking Lake Erie at Buffalo, Dunkirk and Erie, but the grand rivalry is between lake Erie and Ontario, and it is to the superior natural advantages of the latter, as regards position and navigation almost uninterupted throughout the year, that the Great Western railway will be indebted for its importance as forming part of the best avenue to the western States.
The most striking feature in this route is that a railway from Syracuse to Oswego only 35 miles long, will complete the communication by