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English acres of bog. Of these mass of the peculiar substance we shall transcribe some of the called peat, of the average thickmost instructive.

ness of 25 feet, no where less than “ There are many, we believe, 12, nor found to exceed 42; this who consider the bogs of Ireland substance varying materially in its to be low and marshy tracts of appearance and properties, in procountry,not very dissimilar in their portion to the depth at which it composition from the fens of Lin- lies; on the upper surface, covered colnshire; others, aware that the with moss of various species, and substance of which they are form- to the depth of about ten feet, ed greatly differs from that of the composed of a mass of the fibres fen districts, attribute nevertheless of different vegetables in different the origin of both to pretty nearly stages of decomposition proporthe same causes; while an opinion, tioned to their depth from the surmore prevalent, and perhaps not face, generally however too open less erroneous than either of the in their texture to be applied to foregoing, attributes their forma- the purposes of fuel : below this, tion to fallen forests, which are generally lies a light blackish supposed at some former period 10 brown turf, containing the fibres have covered these districts, and of moss still visible, though not to have been destroyed either by perfect, and extending to a further the effects of time, or by hostile depth of perhaps ten feet under armies in the early wars of Ire

this. In the instance exhibited in land.

the section at the close of Mr. The facts stated in Mr. Grif- Griffith's report, are found small fith's report are obviously incon- branches and twigs of alder and sistent with any of these supposi- birch; but we do not understand tions; the bogs which he has sur- him as being of opinion that such veyed being every where in ele- is by any means generally the case. vated situations, and the trees At a greater depth the fibres of which have hitherto been so con- vegetablematter cease to be visible, stantly found buried in the edges the colour of the turf becomes of these bogs, where alone it is blacker, and the substance much probable they have generally been more compact, its properties as sought for, are very rarely to be fuel more valuable, and gradually found in the interior parts, at least increasing in the degree of blackof this district.

ness and compactness proportionWithout entering in this report ate to its depth. Near the bottom into any inquiry as to the origin of the bog it forms a black mass, of these peat bogs, we are however which when dry has a strong reanxious to give such persons as semblance to pitch, or bituminous have not had an opportunity of coal, and having a conchoidal fracexamining them, some idea of the ture in every direction, with a general appearances which they black shining lustre, and suscepactually present.

tible of receiving a considerable It appears from Mr. Griffith, polish. Immediately below this that each of the four bogs included Jower stratum there is generally in the subject of his report, is a found a thin stratum of yellow or

blue clay, varying in thickness bogs from which the water may from one to six feet; in some not be discharged into rivers in places the peat rests on a thinner their irnmediate vicinity, and with stratum of yellowish white marl, falls adequate to their drainage; and containing upon an average about we observe, in the instance of the 60 per

cent. of calcarious matter. bog of Timahoe, that a part of its This stratum of clay in this dis- water is discharged into the sea at trict universally rests on a solid Drogheda, and another part below mass of clay and lime-stone gravel Waterford.” mixed together, and extending to an unknown depth.

We should further consider the REPORT MADE TO THE INSTIpeat moss as partaking in its ge

TUTE, &c. ON WRITING INK. neral nature of the property of From Annales de Chimie, in the sponge, completely saturated with

Philosophical Magazine. water, and giving rise to different streams and rivers for the discharge The object proposed by M.Tarry of the surplus waters which it re- in his memoir is to explain : ceives from rain or snow. These 1. The processes employed for streams in this district almost uni- discharging writing from paper. versally have worn their channels 2. The processes for reviving through the substance of the bog writings which have been appaa down to the clay or limestone gra- rently obliterated, vel underneath, dividing the bog 3. The best way to improve into distinct masses, and present- common ink. ing in themselves the most proper 4. Finally, the discovery of an situations for the main drains, and ink which should resist all chewhich, with the assistance of art, mical agents. may be rendered effectual for that We shall now give an abridgepurpose.

ment of these four articles. Such is the internal structure of the bogs in this district.

Viewing them externally they Processes for discharging Writing. present surfaces by no means level, The art of discharging writing but with plains of inclination am- is very ancient, and the means emply sufficient for their drainage. ployed are very simple. In fact, The highest summit of any part

we know that it is sufficient to of the bogs in this district is 298 moisten a written pa feet above the level of the sea, acid, when the writing will grataken at an ordinary spring-tide in dually disappear. But all the acids the bay of Dublin ; while the low. cannot be employed with equal est point any where on their sur- success. Some leave a stain on the face is 84 feet lower than the paper, which is not easily removhighest, and therefore 214 feet ed; others corrode, and render the above the level of the sea. It re- paper unserviceable. The way to quires a mere inspection of the avoid ihese inconveniences is to map and sections to be convinced make choice of an acid which shall that there is no part of these act on the writing only, without

ARTICLE I.

with any

ARTICLE II.

injuring the paper, or giving it a which the acids have formed with colour different from that which the particles of ink which have it had before it was written upon. been discharged.

In order to discover such of the M. Tarry, at the conclusion of acids as are best suited for the this article, does not fail to observe, operation in question, the author that China ink does not act like determined to submit common common ink with the acids, as its writing ink to the action of differ- composition is quite different from ent acids, and to observe carefully that which we use for writing of the phænomena which these bodies all kinds. So far from the acids present at the time of their mix. attacking China ink, they make it, ture. According to him, the sul- on the contrary, of a deep black : phuric acid easily takes out writ- it cannot be discharged therefore ing, but at the same time it gives without erasing it. an oily tint to the paper.

The acid oxalate of potash produces more certain and more prompt effects. The oxygenized

Processes for ascertaining what muriatic acid, if it be newly made,

Writing has been substituted for seems to be preferable to the above

something taken out, and Metwo acids, because at the same

thods of reviving the Writing time that it takes out the writing,

which has disappeared. it bleaches the

paper

without aller- All the methods which have ing it.

been given for discharging writing It is not the same case with the consist, as abovementioned, in denitric acid, which always takes out composing the ink, and in forcing the ink, but soon penetrates the its constituent parts to form other paper, and forms above it undu- combinations. These combinalated lines of a yellow colour. tions, being decomposed in their

We may succeed, however, in turn by different agents, may resoftening both these effects, by gain a tint, which, if it be not that taking the precaution to dilute the of ink, at least exhibits a shade nitric acid with a sufficient quan- which becomes perceptible enough tity of water, or to wash the paper for ascertaining the letters and immediately after the writing has words which had been traced on been taken out.

the paper before it was touched by A mixture of the muriatic and the acids. nitric acids has but a slow action The gallic acid is, according to upon writing. It bleaches the the author, one of those agents, paper, and does not oppose its which in this case succeeds very desiccation, as when we employ well. the nitric acid alone.

The liquid prussiate of lime also In general, whatever be the kind produces a good effect. of acid employed to discharge

It is the same case with the alwriting, it is always proper, when kaline hydrogenated sulphurets. the operation is performed, to dip But it is very certain that we never the paper in water, in order to obtain any success from the emdissolve the new combinations ployment of these agents, when

we have left any acid long in con- ink, according to our author, com. tact with the writing, and parti- bines every advantage: but we cularly if we have washed the must observe, that it is no more paper afterwards.

exempt than the rest from being In short, we may easily conceive, dissolved in the acids, and in this that in this case the constituent respect it has an inconvenience parts of the ink which were com- which those who wish to discharge bined with the acid, and had form- writing from paper know very well ed with it compounds soluble in how to profit by. This circumwater, having been taken up by stance, no doubt, induced M. this fluid, ought not to leave any Tarry to make some new experitrace of their existence longer; ments, in order to obtain an ink and consequently it is impossible which should be inalterable by chethat the agents employed for dis- mical agents; and he appears to covering them can render them us to have succeeded in his object. visible. It is also for this reason that the

ARTICLE IV. gallic acid, the liquid prussiate of lime, the alkaline hydrogenated Discovery of an Ink which resists sulphurets, and so many other re

the action of chemical agents. agents which have been so much The author describes his invenpraised, can no longer be regarded tion in the following words : as infallible methods for reviving “ My ink is founded upon prinwriting.

ciples different from those of all

others. It contains neither gallARTICLE III.

nuts, Brazil wood, or Campeachy Improvement of Common Ink. gum, nor any preparation of iron;

it is purely vegetable, resists the Most of the inks now in use are action of the most powerful vegeof a bad quality. Some are spon- tables, the most highly concentaneously destroyed; others im- trated alkaline solutions, and, perceptibly lose their black colour, finally, all the solvents. and assume a yellow one ; several,

6. The nitric acid acts very after a length of time, enter into feebly upon the writing performed the paper, and spoil it : lastly, with this ink. The oxymuriatic there are some which are first pale, acid makes it assume the colour and then become very black, of pigeons' dung. After the action

All these differences arise from of this last acid, the caustic alkathe nature of the substances which line solutions reduce it to the cohave been employed in the making lour of carburet of iron : the chaof the ink.

racters of the writing nevertheless Convinced of the advantage of remain without alteration, and it having a good article of this kind, cannot pass through these differthe author commenced a series of ent states, except after long maexperiments, but is forced to admit cerations. The principles of which that he has not discovered any re- it is composed render it incorrupticipe superior to that which has ble, and it can retain its properbeen published by Lewis. This ties many years."

The results which we obtained practice. Potatoes produce more coincided entirely with those of the weight and measure on a given author, and we have no hesitation extent of ground, and may be culin saying, that his is the best we tivated with less expense; still the have ever seen of the kind which

parsnep is found to answer best is called indelible ink. It is liable, for the farmer's purpose. A perch however, to deposit a sediment, a of the island, which is twenty-four disadvantage which we think might square feet, will produce on an be removed by M. Tarry after a average crop seven cabots of potafew more experiments. We have toes, each weighing forty pounds; tried to discharge it with all the the same extent in parsneps will known chemical agents, but with- only average six cabots, which out effect; and we think the in- weigh only thirty-five pounds ventor deserves the thanks of the each, making twenty pounds Institute, and of the community weight in favour of the potatoes, at large.

but they are not so nutritious as

parsneps. ON THE CULTURE OF PARSNEPS. Parsneps will thrive almost any

By Charles Le Hardy, Esq. of where, but better in a deep stiff the Island of Jersey.

loam. They are generally culti

vated in the island after a crop of From the Transactions of the So- barley, in the following manner : ciety of Arts.

At the end of January, or the beHaving observed in the book of ginning of February, the soil, which premiums offered by the Society, requires for this purpose to be stirthat they wished for information red from the bottom, is either dug on the culture of Parsneps, which with spades after a skimming are much used in the island of plough, or with two ploughs of Jersey; as having practised it for different shapes, following one many years, I take the liberty to another. The latter of the two, incommunicate what I know on the vented some years ago by a farmer subject, with the result of some in the island, will go to a depth of comparative experiments. fifteen inches. In both these ways

The culture of parsneps and the neighbouring farmers assist beans is looked upon as one of each other : in the season, it is the regular courses of crops in the not uncommon to see forty or fifty island. There is no farmer, be men in one field, digging after a the extent of his grounds ever so plough. When the large plough is small, who does not yearly plant used, fewer men are required, but a proportionate quantity, for the more strength of cattle: two oxen purpose of fattening his hogs and and six horses are the team genecattle, or feeding his milch cows. rally used. Those days are reckon

A few years ago, the culture of ed days of recreation, and tend to potatoes was substituted by some promote social intercourse among farmers to that of parsneps, and

chat class of men. apparently with advantage; but After the ground has been tilled further experience has brought in this way, it is corasely harrowthem back again to th former ed, and a sufficient number of wo

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