74 



THE CIVIL ENGINEER AND ARCHITECT'S JOURNAL. 



pxpcrinipiits, that the effect of time in incroiisiug the deflection is noted. After 

 tlio Plastic limit is passed the deflection increases with the time which the beam 

 is loaded, the amount i>f this increase is recorded in most of these experiments. 

 The council cannot but regret that Lieutenant Denison should have returned 

 to this country before the very extensive series which he had contemplated, 

 and for whicli he had made preparation was complete ; his intention of deter- 

 mining the change of strengtli and the amount of shrinkage betwixt green and 

 drv was thus unfortunately frustrated ; and they most earnestly concur with 

 him in the expression of hopes that officers and others employed in the colo- 

 nies will be induced to turn their attention to this subject. They point out 

 tlie above communication with especial pleasure as an example to other 

 military engineers, of the very valuable services which their opportunities will 

 enable them to render to the science of the civil engineer. 



The other communication by Mr. Bramah is also a valuable addition to our 

 knowledge, undertaken with a view of verifying the principles assumed in the 

 widely-circulated work of Tredgold on Oast Iron ; they surpass every other 

 series in existence in their extent — the number of experiments being nearly 

 1.^00, and in the care taken to ensure accuracy, since two similar specimens of 

 each beam were made the subject of experiment. 



The principles, with the view of establishing which this series of experiments 

 were iindertaken, are, that the forces of compression and extension are eiiual 

 within the elastic limit, and that consequently a triangular beam, provided it 

 is not loaded beyond this limit, will have the same amount of deflection 

 whether the base or apex be uppermost, and a flanged beam the same defltclion, 

 whether the flange be at the top or the bottoni. 



This communication is accompanied by some valuable observations by your 

 associate, Mr. A. H, Renton, pointing out the agreement whicli subsists 

 between the experiments and the results of the formula of Tredgold. The 

 council have peculiar pleasure in pointing out the preceding, as communica- 

 tions of a kind on which they conceive the Telford medals mav be most 

 worthily bestowed. The undertaking a series of observations and experiments 

 «ith a view of establishing important physical principles, and froni a desire 

 after the truth, is an object worthy of the highest approbation of this institution. 



A silver medal has also been awarded to yonr member, Mr. Green, for his 

 communication on the Canal Lifts on the Grand Western Canal; to your 

 member, Mr. Harrison, for his communication on the Drops on the Stanhope 

 and Tyne Railway, and to your associate, Josiah Richards, for his most ela- 

 liorate drawing of the Rhymney Iron Works. 



The perpendicular lifts erected by Mr. Greeg on the Grand Western Canal 

 involve some ingenious applications of simple principles, and presejit maiiv 

 considerations of interest to the civil engineer. The principles of their con- 

 struction are simple, and the economy of construction and saving both in time 

 and water gives them great advantages in certain cases over locks for the 

 purposes of canal navigation. 



The Drops on the Stanhope and Tyne Railway for the purpose of shipping 

 coals, present another instance of simple mechanical adaptation. These have 

 several points in common with the lifts just spoken of ; the original drawing 

 of these by Mr. Harrison is an exceedingly beautiful example of what drawings 

 of this nature ought to be. 



Of the drawing of the Rhymney Iron Works by Josiah Richards, it would 

 be difficult to speak in too high terms ;-it is a most elaborate drawing, exhibit- 

 ing all the details of the manufacture of iron. The institution has not yet 

 received the description which will be necessary to render the communication 

 comj>lete ; but the council have the gratitication of stating that yonr associate, 

 Mr. Uowles, the chairman of the company, has promised that Mr. Richards 

 shall be furnished with every facility towards completing a commmiication 

 which, they doubt not, w ill be a most Aaluable acnuisilion to the records already 

 existing in the institution. 



Tile council have also awarded a silver medal to Francis Whishaw for his 

 History of Westminster Bridge. Of the great labour and research of Mr. 

 Whishaw in collecting these documents, it would be difficult to speak in adc- 

 (|iiate terms. The history is extracted from voluminous records contained in 

 the Bridge-office, and you are indebted also to the kindness of your member, 

 Mr. Swinbunie, for the facilities which he furnished the author in the execu- 

 tion of his difficult task. The history of this bridge, the only one of the old 

 bridges now remaining, is interesting to the general reader no less than to tlie 

 engineer. The difficulties which presented themselves gave rise to contrivances 

 then for the first time brought into use, of which the introduction of caissons 

 is not the least remarkable. The difficulties and progress of the work are well 

 set forth in the reports of I.abelye, of which the more interesting arc embodied 

 in this communication ; and the account of the work furnishes a very complete 

 history of the state of this department of practical engineering a century ago. 



This communication accompanied by an atlas of eleven drawings showing 

 the site and various details of the constniction of the bridge is one of those 

 historical records which it is especially the object of this institution to collect, 

 and which, from the labour and research employed upon it called for this 

 mark of approbation of the council. 



The institution received during last session from your member Mr. Reudel, 

 a very elaborate and beautiful set of drawings, accompanied by a suitable 

 description of the Torpoint Floating Bridge. This interesting communication 

 is fresh in the recollection of most, and it would be difficult to speak in too 

 liigh terms of the forethought, skill, and design, displayed in the construction 

 lit these bridges, and the perfect success which has attended their establish- 

 ment. It does not often happen that the same individual has the genius to 

 in vent and the good fortune to see his invention brought into general use. In 

 this respect Mr. Reiidel has been singularly lorlnnate, as these bridges have 

 been already established in several difficult and dangerous passages. It would 

 be foreign to the present occasion to dwell more at length on this invention ; 

 but the council feel that in awarding a sBver medal to Mr. Rcnde), accompa- 



nied by a suitable record of the sense entertained of the benefit conferred by 

 him on the inland communication of the country, this, the highest acknowledg- 

 ment in thi'ir power to make, is most amply merited. 



A bronze medal has been awarded to your associate, Mr. Ballard, for the 

 drawing of his ice-boat, and description of his method it breaking ice by 

 forcing it upwards ; this simple method is a])plicable ai about one-third the 

 labour of the ordinary ice-boat. A bronze medal has also been awarded to 

 Thomas Macdoug.il Sniith, for his drawing and account of Kdward's, or the 

 Poiit-y-tu-prydd Bridge, in South \^'ales. Mr. Smith being for a short time 

 in the neighbourhood availed himself of this opportunity to make accurate 

 drawings of this curious ami interesting structure. The council would point 

 out this as an exam])le of the way in which every young man may, by avail- 

 ing himself of the opportunities afforded by his professional engagements, for- 

 ward the objects which the institution has in virw ; and they would earnestly 

 impress on all young men the importance of availing themselves of such op- 

 portunities, and o{ recording their observations on every work with which 

 they may be connecteil. This habit is of the greatest advantage to the indi- 

 vidual, .since only by such an habitual self-improvement can any one hope to 

 obtain eminence in the profession. 



The council hare also awarded five guineas to I\Ir. Guy for his method of 

 making perfect spheres; this great desideratum in the mechanical art has 

 been in a great measure supplied by the ingenuity of this individual, and a 

 simple method furnished of readily producing spheres of metal, or other hard 

 substance, with a great degree of accuracy. 



The preceding are (he communications of the last two sessions to which tlie 

 council have awarded premiums. The coumil in disposing of the premiums 

 placed at their disposal by the munificence of your late President, have en- 

 deavoured to select from the great number of communications wliich haAe 

 been brought before the institution, such of each class as especially deserved 

 this mark of distinction. They trust that these ]iremiiims may act as a sti 

 mulus to many, to forwai'd to the iustitulion records of matters of interest to 

 the profession, and ihal thus the object of the noble benefactor of the institu- 

 tion will be fully realized. 



The council cannot dwell on the numerous communications received 

 during the last session, of which an ample account will be found in the 

 Minutes of Proceedings, they cannot however omit to remark on the great 

 interest of the discussions and on the value of the record of opinions and 

 facts which is thus obtained. They would especially refer to the discussions 

 on the duty of steam engines, and on the explosions of steam boilers, as 

 having led to the collection of much valuable matter; the practice of re- 

 cording the minutes of conversation is almost peculiar to your institution, 

 and is calculated in an especial manner to forward the interests of practical 

 science. 



Life of Telford. — The council, in reviewing the events of the past year, 

 cannot omit to express their gratification at the publication of the Life and 

 Works of Telford. Every thing connected with his name is interesting to 

 this institution, and the life and works of so distinguished a man, written 

 by himself, cannot fail to be received with the gieatest satisfaction by all who 

 knew him or are able to appreciate his works. Through the kindness of your 

 honorary member, Mr. Rickman, the editor of the life and works, and acting 

 executor of Mr. Telford, the institution has been put in possession of two 

 copies of this valuable work. 



Moiiumetit of Telford The council have also the satisfaction of announc- 

 ing through tile medium of this report, that the monument to Telford is 

 nearly finished, and that a jdace has been found for it in \\'estminster Abbey. 

 The site which the Telford committee have selected and hope to obtain, is 

 one well adapted for the statue, and they trust that by the next annual 

 meeting the nmnument will be placed among those who, by the benefits con- 

 ferred on their country, have justly deserved this tribute of respect. 



Charles Teiiuant. — The institution has to regret the loss by death of Mr. 

 Charles Tcnnant, of Glasgow, the eminent practical chemist. Mr. Tennant 

 was born at Gleiiconna, in Ayrshire, in 1767, and commenced his career as 

 an improver in the chemical arts before the end of the last century. The 

 great revolution in the practice of bleaching which then occurred was carried 

 out by the discoveries made by him, first of the solution of chloride of lime, 

 and afterwards of the dry cliloride of lime or bleaching powder, — an in- 

 estimable gift to the arts with which the name of Mr. Tennant will always 

 be associated. The chemical works of St. RoUox, near Glasgow, which now 

 form st> conspicuous a monument of his energy and succes?, were erected 

 for the purpose of manufacturing this article, for wliich he held a patent. 



The manufacture of sulphuric acid, and of alkali from salt, was also 

 greatly improved at St. RoUox, and first conducted there on a scale com- 

 mensurate with their national importance. The manufacturing interests of 

 this country possess an advantage in the extraordinary cheapness of these and 

 other chemical products, which they owe in a great degree to Mr. Tennant's 

 scientific talents, and activity as a manufacturer. 



The arts are deeply indebted to Mr. Tennant for other benefits, particu- 

 larly for his exertions in removing the duty on salt. This he ultimately 

 succeeded in accomplishing, after a struggle of many j-ears with the kelp 

 proprietors. Few legislative enactments have been so binieficial to the 

 country, as is well attested by the immense increase of alkali manufactories. 



For some years past, Mr. Tennant left the chief management of his manu- 

 facturing afl'iiirs to his sons, and devoted a great portion of his energetic mind 

 to the welfare of bis fellow citizens, among whom he was considered a leader 

 in every idiilanlliropic undertaking. 



The success of railway undertakings occupied latterly much of his time 

 and attention ; the last great struggle in which he was engaged was in favour 

 of the Edinburgh and Glasgow line, the passing of the bill for which he had 

 the happiuessto live to sec. He died at his house in Glasgow on the 1st of 



