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PROJECTS AND USEFUL INVENTIONS.

Proposed Drainage of the Bogs in bogs of less extent than 500 acres ; in Ireland.

its form resembling a broad belt drawn

across the centre of Ireland, with its Commissioners having been appoint- narrowest end-nearest to the capital, edin Ireland for the purpose ofenquiring and gradually extending in breadth as into the practicability of this scheme, it approaches to the western ocean, the first report on the subject was de. This great division of the island ex. livered to the House of Commons in tending from east to west, is traversed the summer of 1810, from which the by the Shannon from north to south, following particulars concerning the and is thus divided into two parts ; of nature and extent of those morasses these, the division to the westward of are extracted.

the river contains more than double “ An object, on the due attainment the extent of the bogs which are to of which depended in a great degree be found in the division to the eastthe success of our undertaking, was ward ; so that if we suppose the whole the proper division of the bogs of Ire of the bogs of Ireland (exclusive of land into the districts referred to in the

mere mountain bog, and of bogs under first article of the instructions ; and 500 acres) to be divided into twenty further, to determine in what part we parts, we shall find about seventeen of should first apply those means entrust. them comprized within the great divi. ed to us, and which we at once per. sion we have now described, twelve to ceived were utterly inadequate to the the westward, and five to the eastward execution of any plan that should em- of the Shannon ; and of the remaining brace the entire extent of Ireland. three

about two are to the south, “ From inspection of the map execu. and one to the north of this division. ted by General Vallency, we were ena- Of the positive amount of their conbled to consider these bogs as forming tents we have as yet no data that can one connected whole, and to come to enable us to speak with any precision ; the general conclusion, that a portion but we are led to believe, from various of Ireland, of little more than one- communications with our engineers, fourth of its entire superficial extent, that the bogs in the eastern division and included between a line drawn of the great district above described from Wicklow-head to Galway, and an amount toabout 260,000 English acres, other drawn from Howth-head to Sli- which, on the proportion already men.' go, comprises within it about six- tioned, would give rather more than one sevenths of the bogs in the island, ex. million of English acres as the total clusive of mere mountain-bogs and contents of the bogs of Ireland; ex

parts,

aluding, however, from consideration considerable obstacles to improvement, mere mountain bogs, and also all bogs the overcoming of which would in itof less extent than 500 acres, of each self demonstrate the practicability of of which description the amount is the improvement of the bogs of Íre. very

considerable; of the extent of the land in most other cases." latter some idea may be formed from The commissioners then proceed to a fact which we have learned from Mr state the particulars of their parcelling Larkin; that in the single county of out the bogs to be surveyed, to differCavan, which he has surveyed, there ent engineers, with the

pay

allotted to are above 90 bogs, no one of which them and the persons employed unexceeds 500 Irish acres, but which ta- der them; and they then give some obken collectively contain about 11,000 servations derived from the first report Irish, which is equivalent to above delivered in, that of Mr Griffith, to 17,600 English acres, besides many whom was consigned a district formsmaller bogs varying in size from five ing the eastern end of the Bog of Allen, to twenty acres.

and containing 36,430 English acres “ Most of the bogs which lie to the of bog. Of these we shall transcribe eastward of the Shannon, and which some of the most instructive. occupy a considerable portion of the “ There are many, we believe, wha King's county and county of Kildare, consider the bogs of Ireland to be low are generally known by the name of and marshy tracts of country, not very the Bog of Allen : it must not how. dissimilar in their composition from ever be supposed that this name is ap- the fens of Lincolnshire; others, aware plied to any one great morass : on the that the substance of which they are contrary, the bogs to which it is ap- formed greatly differs from that of the plied are perfectly distinct from each fen districts, attribute nevertheless the other, often separated by high ridges origin of both to pretty nearly the same of dry country, and inclining towards causes; while an opinion, more prevadifferent rivers, as their natural direc- lent, and perhaps not less erroneous, tions for drainage, so intersected by than either of the foregoing, attributes dry and cultivated land, that it may their formation to fallen forests, which be affirmed generally, there is no spot are supposed at some former period of these bogs, to the eastward of the to have covered these districts, and to Shannon, so much as two Irish miles have been destroyed either by the ef. distant from the upland and cultivated fects of time, or by hostile armies in districts.

the early wars of Ireland. “With this first and general view of « The facts stated in Mr Griffith's the subject, we had no hesitation in se report are obviously inconsistent with lecting at once the whole of the east- any of these suppositions ; the bogs ern portion of the great district above which he has surveyed being every referred to, as the object of our first where in elevated situations ; and the enquiries, forming in itself one whole, trees which have hitherto been so conwhose parts had more or less connec- stantly found buried in the edges of tion with each other, lying in the cen- these bogs, where alone it is probable tre of Ireland, in the immediate vicini. they have generally been sought for, ty of some of the richest and best cul

are very rarely to be found in the inte tivated counties; intersected also by rior parts, at least of this district. the two great lines of navigation, the “Without entering in this report in. Grand and the Royal canals, and pre- to any enquiry as to the origin of these senting in common apprehension very peat bogs, we are however anxious to

gire such persons as have not had an ness from one to six feet ; in some opportunity of examining them, some places the peat rests on a thinner straidea of the general appearances which tum of yellowish white marl, containthey actually present.

ing upon an average about 60 per cent. « It appears from Mr Griffith, that of calcarious matter. This stratum each of the four bogs included in the of clay in this district universally rests subject of his report, is a mass of the on a solid mass of clay and limestone peculiar substance called peat, of the gravel mixed together, and extending average thickness of 25 feet, no where to an unknown depth. less than 12, nor found to exceed 42; “Weshould furtherconsider the peat this substance varying materially in its moss as partaking in its general nature appearance and properties, in propor- of the property of sponge, completely tion to the depth at which it lies ; on saturated with water, and giving rise the upper surface, covered with moss to different streams and rivers for the of various species, and to the depth of discharge of the surplus waters which about ten feet composed of a mass of it receives from rain or snow. These the fibres of different vegetables in dif- streams in this district almost universally ferent stages of decomposition propor- have worn their channels through the tioned to their depth from the surface, substance of the bog down to the clay generally, however, too open in their or limestone gravel underneath, divi- . texture to be applied to the purposes ding the bog into distinct masses, and of fuel : below this, generally lies a presenting in themselves the most prolight blackish-brown turf, containing per situations for the main drains, and the fibres of moss still visible, though which, with the assistance of art, may not perfect, and extending to a further be rendered effectual for that purpose. depth of perhaps ten feet under this. “ Such is the internal structure of In the instance exhibited in the sec- the bogs in this district. tion at the close of Mr Griffith's re- “ Viewing them externally they preport, are found small branches and sent surfaces by no means level, but twigs of alder and birch ; but we do with planes of inclinations amply sufnot understand him as being of opi. ficient for their drainage. The highnion that such is by any means ge- est summit of any part of the bogs in nerally the case. At a greater depth this district is 298 feet above the level the fibres of vegetable matter cease to of the sea, taken at an ordinary springbe visible, the colour of the turf be- tide in the bay of Dublin ; while the comes blacker, and the substance much lowest point any where on their sur more compact, its properties as fuel face is 84 feet lower than the highest, more valuable, and gradually increa. and therefore 214 feet above the level sing in the degree of blackness and com- of the sea. It requires a mere inspec. pactness proportionate to its depth. tion of the map and sections to be Near the bottom of the bog it forms convinced that there is no part of these a black mass, which, when dry, has a bogs from which the water may not strong resemblance to pitch, or bitu- be discharged into rivers in their imminous coal, and having a conchoidal mediate vicinity, and with falls ade. fracture in every direction, with a quate to their drainage ; and we obblack shining lustre, and susceptible serve, in the instance of the bog of of receiving a considerable polish. Im. Timahoe, that a part of its water is mediately below this lower stratum discharged into the sea at Drogheda, there is generally found a thin stratum and another part below Waterford." of yellow or blue clay, varying in thick

mon ink.

REPORT MADE TO THE INSTITUTE, more certain and more prompt effects. &c. ON WRITING INK. The oxygenized muriatic acid, if it be

newly made, seems to be preferable to From Annales de Chimie. the above two acids, because at the

same time that it takes out the writing, The object proposed by Mr Tarry it bleaches the paper without altering in his memoir is to explain,

it. 1. The processes employed for dis- It is not the same case with the nicharging writing from paper.

tric acid, which always takes out the 2. The processes for reviving wri- ink, but soon penetrates the paper, tings which have been apparently ob. and forms above it undulated lines of literated.

a yellow colour. 3. The best way to improve com- We may succeed, however, in sofa

tening both these effects, by taking 4. Finally, the discovery of an ink the precaution to dilute the nitric acid which should resist all chemical agents. with a sufficient quantity of water, or

We shall now give an abridgment to wash the paper immediately after of these four articles.

the writing has been taken out.

A mixture of the muriatic and niARTICLE I.

tric acids has but a slow action upon Processes for discharging Writing. writing. It bleaches the paper, and

does not oppose its desiccation, as The art of discharging writing is when we employ the nitric acid alone. very ancient, and the means employed In general, whatever be the kind of are very simple. In fact, we know acid employed to discharge writing, it that it is sufficient to moisten a writ. is always proper, when the operation ten paper with any acid, when the is performed, to dip the paper in water, writing will gradually disappear. But in order to dissolve the new combinaall the acids cannot be employed with tions which the acids have formed with equal success. Some leave a stain on the particles of ink which have been the paper, which is not easily removed; discharged. others corrode, and render the paper : Mr Tarry, at the conclusion of this unserviceable. The way to avoid these article, does not fail to observe, that inconveniences is to make choice of an China ink does not act like common acid which shall act on the writing ink with the acids, as its composition only, without injuring the paper, or is quite different from that which we giving it a colour different from that use for writing of all kinds. So far which it had before it was written from the acids attacking China ink, upon.

they make it, on the contrary, of a In order to discover such of the deep black : it cannot be discharged acids as are best suited for the ope. therefore without erasing it. ration in question, the author determi. ned to submit common writing ink to the action of different acids, and to observe carefully the phænomena which Processes for ascertaining what Writhese bodies present at the time of their ting has been substituted for some. mixture. According to him, the sul- thing taken out, and Methods of rephuric acid easily takes out writing, viving the Writing which has disapbut at the same time it gives an oily peared. tint to the paper. The acid oxalate of potash produces All the methods which have been

10

ARTICLE II.

given for discharging writing consist, destroyed; others imperceptibly lose as abovementioned, in decomposing their black colour, and assume a yel. the ink, and in forcing its constituent low one ; several, after a length of parts to form other combinations. time, enter into the paper and spoil it ; These combinations, being decompo- lastly, there are some which are first sed in their turn by different agents, pale, and them become very

black. may regain a tint, which, if it be not All these differences arise from the that of ink, at least exhibits a shade nature of the substances which have which becomes perceptible enough for been employed in the making of the ascertaining the letters and words ink. which had been traced on the paper Convinced of the advantage of habefore it was touched by the acids. ving a good article of this kind, the

The gallic acid is, according to the author commenced a series of experiauthor, one of those agents, which in ments, but is forced to admit that he this case succeeds very

well.

has not discovered any recipe superior The liquid prussiate of lime also pro. to that which has been published by duces a good effect.

Lewis. This ink, according to our It is the same case with the alkaline author, combines every advantage ; hydrogenated sulphurets. But it is but we must observe, that it is no more very certain that we never obtain any exempt than the rest from being dissuccess from the employment of these solved in the acids, and in this respect agents, when we have left any acid it has an inconvenience which those long in contact with the writing, and who wish to discharge writing from particularly if we have washed the pa. paper know very well how to profit per afterwards.

by. This circumstance, no doubt, inIn short, we may easily conceive, duced M. Tarry to make some new that in this case the constituent parts experiments, in order to obtain an ink of the ink which were combined with which should be unalterable by chemi. the acid, and had formed with it com- cal agents ; and he appears to us to pounds soluble in water, having been have succeeded in his object. taken up by this fluid, ought not to leave any

trace of theirexistence longer; and consequently it is impossible that the agents employed for discovering them can render them visible.

Discovery of an Ink which resists the It is also for this reason that the Action of Chemical Agents. gallic acid, the liquid prussiate of lime, the alkaline hydrogenated sulphurets, The author describes his invention and so many other re-agents which in the following words : have been so much praised, can no My ink is founded upon princilonger be regarded as infallible me. ples different from those of all others. thods for reviving writing.

It contains neither gallnuts, Brazil wood, Campeachy gum, nor any preparation of iron : it is purely vegetable, resists the action of the most powerful

vegetables, the most highly concentraImprovement of Common Ink. ted alkaline solutions, and, finally, all

the solvents. Most of the inks now in use are of

« The nitric acid acts very feebly a bad quality. Some are spontaneously upon the writing performed with this

ARTICLE IV.

ARTICLE III.

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