'844.] 



THE CIVIL ENGINEER AND ARCHITECT'S JOURNAL. 



393 



Royal Agricultural Society, a great many agriculturists and a g eat 

 many engineers consifiered the appointment as little better than a 

 sinecure, perhaps nothing more than the giving to Mr. Parkes a sound- 

 ing designation. We cannot say that we ourselves anticipated the 

 exertions he has since made. Onlv to instance his last communica- 

 tion in the transactions of the Royal Agricultural Society will be suffi- 

 cient to give Lin intimation of what may be done. He therein dis- 

 cusses the size of draining tiles, and from a careful investigation of 

 the quantity of water falling and the quantity to be conveyed, 

 he has been enabled to establish on a scientific and practical basis the 

 necessity for greatly reducing the size of the tiles. The economical 

 results accruing from this will be at once seen, the saving in material, 

 labour and fuel in forming the tiles, a reduced cost to the landowner 

 and farmer, a diminished cost for cartage, and for repairs. Thus a 

 most important diminution is obtained in the cost of all large draining 

 operations, a grand point, when we consider that the large outlay is 

 the great obstacle to the extension of draining. Yet this is but an 

 earnest of what engineering can do for agriculture ; agriculture has, 

 hitherto, been too much treated as a rule of thumb, petty chandler's shop 

 pursuit, even when carried out on large farms, but the extension of 

 farms admits the operations of the engineerwithgreatadvantage. The 

 farmer is in truth a manufacturer, there is nothing mystic, nothing 

 extra-economical in his pursuits, he is as much a manufacturer as the 

 cotton or woollen manufacturer, and his operations must be conducted 

 by machinery as good, as efficient, as cheap and as saving, and this, to 

 a great degree, is yet to be done, although we have from Scotland a 

 good deal of experience as to its advantage. Much ingenuity has been 

 devoted to spades, and ploughs, cultivators, harrows, and thrashing 

 machines, but the economical working of a farm as a whole, the pro- 

 per application of power, and its adaptation to the resources of the 

 locality, have been little studied, and here again the mechanical en- 

 gineer will find wide scope. The possession of water power on the 

 spot, and the power to transport to market a dressed article, instead 

 of the material in its raw and rough state, may often make production 

 profitable, which otherwise could not be undertaken without consider- 

 able loss. 



Drainage is indeed a grand engineering operation, and with what 

 advantage it can be followed as a pursuit Mr. Smith, of Deanston, has 

 well shewn. It is evident, from the instance of Mr. Josiali Parkes' 

 exertions just adduced, that draining canout cheaply be carried out 

 empirically, for either we run the hazard of wasting money by too 

 great an expenditure of material, or we jeopardize our proceedings on 

 the other lianil by making insufficient provision. The ground must be 

 well levelled, its nature examined with the eye of a geologist, so as to 

 ascertain the causes of any extra supply of water and the means of 

 preventing it, and also the most convenient natural outlet, whether by 

 the usual water-courses, by means of one of the geological dikes which 

 intersect the country, or perhaps even by an absorbent artesian well to 

 reach some lower sandy stratum. While, on the one hand, the well- 

 trained practitioner will be able successfully to deal with a difficult 

 case, to relieve cheaply and efficiently a moss or submerged district, 

 the blunderer may bore so as to get at more water, or expend much 

 money without obtaining any adequate result. The artesian well 

 places at the disposal of the engineer well trained in geology as com- 

 plete a command over the drainage of the earth as it is possible to 

 conceive, it enables him to select his water-course at any required 

 depth, as the balloonist chooses his course, either by ascending or 

 descending, among the various strata of the atmosphere. Not only 

 can the engineer discharge below water which cannot be discharged 

 above, but he can bring up, if need be, further supplies of water from 

 the subterranean strata, and, a point of great importance, water of dif- 

 ferent properties. Whereas, we may have above water strongly im- 

 pregnated with mineral substances injurious to vegetation, we may 

 get rid of that and obtain a wholesome water from a lower stratum, or 

 a water, perhaps, having some required chemical property, coming, it 

 may be, from a calcareous formation, and holding lime in solution. 

 By acquaintance viith the laws governing the temperature of strata, 

 and the progressive increase of temperature as we descend beneath 

 the surface of the earth, we can procure water of a high temperature, 

 which may be beneficially employed in ccltivation. Here, again, it 

 will be noticed how studies, speculative in their origin, are ultimatelv 

 made to bear practical fruits. The ill-informed man, who thinks 

 there is nothing but practice, and snaps his finger at all theory, for- 

 getting that the two cannot be safely associated, might have 

 smiled in derision at the long and serious discussion as to the 

 temperature of wells, and the height of tlie thermometer in mines. 

 We may here observe, however, that even with regard to the ventila- 

 tion of mines the study is important to the practical man, though we 

 have a better proof still. We will, however, call the attention of the 

 mining engineer to another result accruing from philosophic investi- 



gation. It has been well ascertained' that the state of the atmos- 

 phere has a considerable influence on the c mses of explosions in 

 mines, the barometer having in cases of such accidents been observed 

 to fall suddenly, while, in many cases, the discharge of hydrogen gas 

 is found to be most intense and powerful while the wind blows from 

 the S. W. and the barometer is low, but diminishes when the baro- 

 meter is rising. The sudden change in the weight of the atmosphere, 

 and consequent pressure of the gases, is, indeed, with scientific men, 

 held to be a powerful predisposing cause to those fatal colliery cata- 

 strophes, of which one so serious has lately occurred. So far, too, as 

 we are able to recollect these casualties have happened in paiticniar 

 months, and at any rate we think it incumbent on the superintendents 

 of collieries to keep a close watch on the barometer, and in case of 

 any sudden and serious fall we think it should be incumbent on the 

 managers immediately to stop the workings for the day. At sea very 

 great benefit has been found from the observation of sudden changes 

 in the barometer in preparing fot hurricanes, so that in well-conducted 

 vessels it is the practice immediately on the change being ascertained 

 to get in readiness for the coming storm. To return, however, to the 

 practical results accruing from a higher temperature of air and water 

 in the lower strata, we find, from Professor Ansled's work, (vol. ii. 

 p. 528,) that advantage has sometimes been taken of the temperature 

 of water from deep springs, conservatories have been warmed, cress- 

 plots cultivated, and fishponds improved, particularly in Germany. 

 At Erfurt, it is stated, the proprietor of a salad ground by availing 

 himself of this means obtains a profit of not less than £12,000 per 

 annum. The great Smith, the father of geology, who was as practical 

 au engineer as he was a skilful man of science, was often called upon 

 to apply his powers of command over subterranean springs and water- 

 courses to important cases of draining. We shall leave Prof. Ansted 

 to state this himself. 



Mr. William Smith, who at the close of the last century had made him- 

 self much more accurately acquainted with the actual order of superposition 

 of the Secondary strata in England than any person then living, was also 

 on^ of the first to apply this knowledge to important practical purposes. 

 About the year 1800 his reputation for " draining on new principles" was 

 thoroughly established in the West of England, and on the occasion of nu- 

 merous landshps taking place near Bath, lie was employed to prevent, if 

 possible, a recurrence of this mischief, vvliich he effected by tunnelling 

 into the hill on which the land was slipping, and intercepting the springs, 

 and then providing a direct and convenient channel, by which the water 

 could be discharged. In the year 1811 Mr. Smitli was again employed 

 to report on a subject of practical science connected with the drainage 

 of strata. About that time numerous canals were being cut in different 

 parts of the West of England, and these, crossing the oolitic hills, were 

 found to be particulary liable to accidents of leakage, being cut througli 

 open jointed, and sometimes cavernous rocks, alternating with water-tight 

 clays. In the passage across the former rocks, and more especially when the 

 summit level of the canal occurs in them, the water escapes almost as fast as 

 it enters, and all the skill of the engineer in puddling, and making an artiti- 

 eial bed, is sometimes exerted in vain, and cannot prevent great and ruinous 

 loss. But the existence of open joints and caverns is by no means the only, 

 nor, indeed, the greatest source of injury, for innumerable small faults or 

 slides traverse the country and confuse the natural direction of the springs, 

 rendering them short in their courses, and uncertain and temporary in their 

 flow, weakening by their irregular pressure every defence that may he op- 

 posed to them, and causing leaks, which let through a portion of the water 

 contained in that level of the canal. 



The general remedy for all these evils was understood by Mr. Smith, and 

 proposed by him for adoption. It is " the entire interception of all the 

 springs which rise from a level above the canal and pass below it through 

 natural fissures and cavities. This is a process re«iuiring great skill and ex- 

 tensive experience ; some of the springs for instance which it is most impor- 

 tant to intercept come not to the surface at all in the ground above the 

 canal, but flowing naturally below the surface through shaken or faulty 

 ground, or along masses of displaced rock which extend in long ribs from 

 the brows down into the vale, emerge or attempt to emerge in tlie banks of 

 the canal ; these no ordinary surface-draining will reach, and none hut a 

 draining engineer, well versed in the knowledge of strata, can successfully 

 cope with such mysterious enemies. But Mr. Smith, confident in his gre'At 

 experience, not only proposed, by a general system of subterraneous excava- 

 tion to intercept all these springs, and destroy their power to injure the 

 canal, but further, to regulate and equalize their discharge, so as to render 

 them a positive benefit. This he would have accomplished by penning up 

 the water in particular natural areas, or pounds, which really exist between 

 lines of fault in most districts, or between certain riJges of clay (' horses,') 

 which interrupt the continuity of the rock, and divide the subterranean 

 water-fields into limited districts, separately manageable for the advantage 

 of man by the skilful adaptation of science." — Professor Phillips' Life of 

 William Smith, p. 69. 



In all those departments of engineering, which have to deal with 



1 Traniactions of Nat. Hlat. Sov. of Northumberland, toI. i. p. 186. 



