150 



THE CIVIL KNGIiNEER AND ARCHITECTS JOURNAL. 



[May, 



Agricultdre. 



Neither must we forget the comparatively recent adaptation of engineer- 

 ing knowledge to the advancement of af;riciilture, and the various imple- 

 ments connected with it, for pli>u;;liing, drilling, iliresliiiig, &i;. Since the 

 improvement in the working of iron, the machines for coiidncting these 

 various operations are constructed with a degree of portubilily. economy, 

 and efficiency which render them of the greatest importance to the farmer, 

 and enable hira to cultivate the soil, as well as to convert its various pro- 

 ducts to domestic purposes, in a much more economical and expeditious 

 manner than formerly, and to derive a greater profit from his exertions. In 

 the construction of agricultural implements, Messrs. Ransorae, May, Cot- 

 tam, Stratton, and others, have greatly distinguished themselves. 



In modern agriculture, uuder-draining forms an important and valuable 

 principle; stagnant water generally has been proved to be injurious lo 

 agriculture, and it is, 1 believe, now universally admitted that without 

 thorough drainage it is impossible to cultivate the soil elfeclually ; for this 

 purpose small drains formed by tiles laia from I foot to 4 feet below the 

 surface, are generally adopted ; the tiles are made by machinery invented 

 by the Marquis of Tweedale, /Vinslie, and others, at a trilling cost ; the 

 surface water is thus conveyed from the land into the adjacent main drains 

 and thence to tlie rivers. Water is the grand natural fertilising agent, and 

 any amount of care in its proper distribution is well bestowed : it is, 

 therefore, worthy of consideration, whether in hilly countries and districts 

 subject to alternations of dry and wet seasons, it would not be advisable 

 to establish large reservoirs for water, to be used during dry seasons for 

 irrigation, in the manner adopted by the ancients ; by this means, districts 

 might be cultivated with advantage, which now are comparatively ste- 

 rile. 



Surveying. 



Land and Maritime Surreijing form an essential department in the pro- 

 fession of a civil engineer; without a correct knowledge of the former, it 

 is impossible for him to lay out and determine in the best manner the pro- 

 per lines of communication in a district, whether by canal, railway, or 

 common road; and without a knowledge of the latter, it is equally diffi- 

 cult for him to decide upon the best situation for a port, and the most 

 advisable means of improving and maintaining it. In these valuable 

 departments much progress has been made. The great Trigonometrical 

 Survey of the British Islands, which is now very nearly completed, is the 

 greatest work of this kind ever undertaken in this country, and serves as 

 a model for minor works of this nature. It was commenced by General 

 Roy in the year 1783, under the direction of the Ordnance Department of 

 the government, and has been subsequently carried on, with equal ability, 

 by General Mudge and Colonel Colby, of the Royal Engineers, under 

 whose direction it now is. This great work, so far as it has proceeded, 

 Las already proved of essential service to the civil engineer, inasmuch as 

 all the towns and villages, the chains of hills, valleys, and rivers, being 

 laid down trigonometrically, his labours, as well as the expenses of his 

 employers, are materially diminished, in tracing out the best lines for 

 railways or other internal communications; instead of having to survey 

 the whole district of his operations trigonometrically, he has only to take 

 the leading points, and to till in the detail of fields, buildings, ^:c., lo a 

 larger scale; and even before incurring this labour he can, with one of the 

 Ordnance maps in his hand, determine in a great measure the general 

 direction and course of his line; notwithstanding this, it is essential for 

 him to have a thorough knowledge of the use of instruments, the theodo- 

 lite, sextant, and transit, the most accurate mode of measuring bases, and 

 to see that those employed under him are competent to their task, and 

 employ the necessary means to ensure accuracy in their surveys. Con- 

 nected with surveying, we must not omit the important department of 

 levelling, for simple as it is, nothing requires greater accuracy, — in fact, 

 upon this being properly done the success of the whole scheme or under- 

 taking in hand may be said mainly to depend ; too much attention, there- 

 fore, cannot be paid to it ; the instruments employed should be of the best 

 construction, simple and substantial, easily adjusted, and kept in good 

 order ; the levels should be referred to one datum and proved in various 

 ways, and recorded in a plain intelligible manner, so that they may at all 

 times be easily referred to. 



Maritime Surveying requires an intimate knowledge of the general laws 

 which govern the tides, the set of the currents, the prevalence and direc- 

 tion of the winds, the soundings, anchorage ground, &c, ; these should be 

 regularly observed for a given period, in order to ascertain every possible 

 variation, and regularly registered and referred to the same datum. For 

 this purpose, self-acting tide-gauges, with a clock apparatus attached to 

 them, for marking the time of high and low water, if placed in proper 

 situations, are extremely valuable: that at Sheerness dockyard, by Mit- 

 chell, and the improved one at Ramsgate harbour, are here worthy of 

 remark. 



Mineral or Underground Surreijing differs from the above in its being 

 necessary to ascertain the dip or angle at which the several strata lay, 

 their general direction and thickness, their quality and value, and the best 

 mode of working them. For laying down the underground survey, tlie 

 magnet and circumferenter are much employed. 



In the investigation of the laws which govern the tides we are much 

 indebted to the valuable scientific researches of our honorary members 

 Lubbock, Whewell, Airy, and others. Connected with the various branches 



of surveying, the construction of philosophical instruments is entitled to 

 an important station ; as without accurate instruments it is impossible to 

 make correct surveys, and for the construction of these we are much in- 

 debted to the lab'jurs of Ramsden, TruughtOD, Dollond, Carey, Simmt, 

 Watkins, Jones, Elliott, and others. 



Drawing. 



Drawing and modelling, although minor, form valuable, and, in fact, 

 indispensable departments in civil engineering ; for unless the various 

 projects proposed to be carried into efiect, are in the first instance correctly 

 delineated upon paper, it is impossible to convey a just idea of them, or 

 to form a correct estimate of the cost. Drawing may be classed under 

 three heads : — mechanical or geometrical drawing, is that whereby the 

 plans and sections are simply represented as they would appear on a plane 

 surface ; perspective drawing consists in representing the objects as they 

 appear when seen from a given distance and height; this kind of drawing, 

 although very useful, and indeed indispensable, to the architect, in order 

 to represent the true effects of light and shade of his different composi- 

 tions, as they would appear when carried into effect, and upon a true per- 

 ception of which, the success of his building will mainly depend, is not of 

 that importance to the engineer, whose works are of a dilfercnt kind, and 

 much more extensive, so that to represent them perspectively would in 

 many cases be impracticable; but inasmuch as in detached portions of 

 his works, such as important bridges, viaducts, machinery, £tc., perspec- 

 tive drawing may be employed with great advantage, it ouglit to be stu- 

 died. Landscape and topographical drawing is also useful, in order to 

 convey lo unscientific persons an idea of a particular locality, in the man- 

 ner they are accustomed to view it, where wnrks are proposed to be exe- 

 cuted, and thus to remove fancied objections which otherwise might be 

 overcome with difficulty ; and this is still more successful witli the appli- 

 cation of colours when applied as seen in nature. These different kinds 

 of drawing should be carefully studied and praciised with accuracy, as 

 they will be found essentially to forward the views of the engineer, and 

 give satisfaction to his employers. 



Although drawing, however, is most valuable, modelling in many cases 

 is essential ; for in the former case the objects are merely represented upon 

 paper, assisted by light and shade and perspective, which, to persons in 

 some measure acquainted with the subject, conveys a tolerably correct 

 idea of what is proposed to be done, but a model represents it (although 

 upon a reduced scale) exactly as it is intended to be, with the different 

 planes, dimensions, and surfaces; hence, nothing, except the work itself, 

 gives such a perfect idea or representation as a model ; it also enables the 

 engineer to detect many imperfections which otherwise wouhl escape his 

 notice ; whenever, therefore, models can be conveniently adopted or em- 

 ployed, it is advisable to do so; and it is gratifying to know that the art 

 of modelling has made considerable progress, so that now they can be 

 obtained at a moderate cost in wood, card-board, plaster, and clay, and 

 will thus be more generally employed. In this department Salter, Ueigh- 

 ton. Day, and others, have attained deserved celebrity. Working models 

 of macliines are extremely useful to give an idea i^f the action of a ma- 

 chine, but we should be cautious in drawing conclusions from the results, 

 for it too frequently happens that a machine succeeds extremely well when 

 tried in a model, but fails when put in practice ; we should, therefore, 

 merely consider the results of working models as guides_to be worked out 

 practically. 



Meteorology. 



The principles of this science, as far as they have yet been determined, 

 claim our particular attention. Without a knowledge of the winds, and 

 the quantity of rain falling in a particular district, we cannot delerniine 

 with precision the proper form and dimensions of moles or piers to resist 

 tiie action of the sea, or of drains to carry ofif water from extensive dis- 

 tricts of marsh land, or of the extent to which it may be necessary to im- 

 prove the channels of rivers; or in carrying lines of railway through a 

 country, to design the works in such a manner that they may withstand 

 the shocks of the elements ; neither can we select the proper kind of oione 

 or other materials for constructing buildings, unless we know the vicissi- 

 tudes of climate to which they may be exposed, or the extent to which 

 they may be acted upon by it. 



In the investigation of the phenomena of this difficult science, we are 

 much indebted to the late Professor Daniell, and to C H. Smith, whose 

 report upon the qualities of the different kinds of stone, as regards their 

 tenacity, hardness, capability of resisting moisture, and durabilily, for the 

 purpose of selecting the best material for the new Houses of Parliament, 

 forms an important and useful example, for which tlie engineer and the 

 architect are much indebted, and the same course should be followed, as 

 far as is practicable, previous to commencing every great work, and in- 

 deed, for the want of it, we now find many magiiiticeut buildings par- 

 tially decayed, which otherwise, would have been in excellent preserva- 

 tion. 



Patents. 



The improvements in manufactures, machinery, and other branches of 

 art, resulting from a great number of curious aud valuable inventions, 

 necessarily gave rise, on the part of the successful inventors, to a desire to 

 secure for themselves and their posterity, as far as is practicable, the bene- 

 fits of their labours. The Government, perceiving and duly appreciating 

 the advantages which not only the inventors theiuselrea, but the nation at 

 large, derived from them, wisely resolved to give every possible eucoa- 



