1S41.] 



THE CIVIL ENGINEER AND ARCHITECT'S JOURNAL. 



287 



and dried, and the 6xing process (which may be deiferred to a subsequent 

 day) is the same as that aheady mentioned. The copies are made by placing 

 the picture upon tlie photographic paper, with a board below and a sheet of 

 glass above, and pressing the papers into close contact by means of screws 

 or otherwise. Aftei a calotype picture has furnished several copies, it some- 

 times grows faint, and no more good copies can then l)o made from it. But 

 these pictures possess the beautiful and extraordinary property of being sus- 

 ceptible of revival. In order to revive them and restore their original ap- 

 pearance, it is only necessary to wash them again by candle-light v\i>h gallo- 

 nitrate of silver, and warm them ; this causes all the shades of the picture 

 to darken greatly, while the white parts remain unaffected. The shaded 

 parts of the picture thus acquire an opacity which gives a renewed spirit 

 and hfe to the copies, of which a second series may now be taken, extending 

 often to a very considerable number. In reviving the picture it sometimes 

 h.ippens that various details make their appearance which had not before 

 been seen, havhig been latent all the time, yet nevertheless not destroyed by 

 their long exposure to sunshine. The author terminates these observations 

 by staling a few experiments calculated to render the mode of action of the 

 sensitive paper more famiUar. 1. Wash a piece of the iodized paper with 

 the gallo-nitrate ; expose it to daylight for a second or two, and then with- 

 draw it. The paper will soon begin to darken spontaneously, and will grow 

 quite black. 2. The same as before, but let the paper be warmed. The 

 blackening will be more rapid in consequence of the warmth. 3. Put a large 

 drop of the gallo-nitrate on one part of the paper, and moisten another part 

 of it more sparingly, then leave it exposed to a very faint daylight ; it will be 

 found that the lesser quantity produces the greater effect in darkening the 

 paper; and in general, it wdl be seen that the most rapid darkening takes 

 place at the moment when the paper becomes nearly dry ; also, if only a 

 portion of the paper is moistened, it will be observed that the edges or boun- 

 daries of the moistened part are more acted on by light than any other part 

 of the surface. 4. If the paper, after being moistened with the gallo-nitrate, 

 is washed with water and dried, a shght exposure to daylight no longer suf- 

 fices to produce so much discoloration ; indeed it often produces none at all. 

 But by subsequently washing it again with the gallo-nitrate and warming it, 

 the same degree of discoloration is developed as in the other case (experi- 

 ments 1 and 2). The dry paper appears, therefore, to be equal, or superior 

 in sensitiveness to the moist ; only with this difference, that it receives a 

 virtual instead of an actual impression from the light, which it requires a 

 subsequent process to develope. 



Plaster Ornaments. — The late Mr. Bernasconi was engaged, we believe, 

 to a greater extent than any other ornamental plasterer of the present cen- 

 tury, under all the leading architects of the day. We were lately induced 

 to pay a visit to his former scene of business, in Alfred Street, Tottenham 

 Court Road, now in possession of Mr. Brown, his son-in-law, who has lately 

 arranged the numerous ornaments bequeathed him by the late possesor. 

 They are well deserving of a visit by the architect ; here he will find Gre- 

 cian, Roman, Gothic, Elizabethan, the Renaissance, Arabesque, and almost 

 evei7 other style of ornaments that have been introduced at Windsor Castle, 

 Buckingham Palace, Pavilion Brighton, Staff'ord Hoii^e, Westminster Abbey, 

 Fonthill, Woburn Abbey, York Minster, Ely Cathedral, and numerous other 

 public buildings and mansions throughout the United Kingdom. 



HZSCEIfliANEA. 



WESTMINSTER BRIDGE. 



On Thursday, 15th ult., the water was admitted into the coffre-dam in- 

 closing the 15th and IGth piers, and the next day a commencempnt was made 

 in removing the clay preparatory to dra'.\ing the piles. It is intended to 

 open two arches for navigation before any further steps are taken with the 

 next dam, which is to enclose one pier only. A deep water channel is now 

 in progress of being made on the north side of the river, in line with the two 

 arches about to be opened, by a steam dredging engine, for the use of navi- 

 gation. The present neglected state of the river not only interferes most in- 

 juriously with the interests of those who navigate it, liut causes the velocity 

 of the current at the latter part of the ebb to be greater than is consistent 

 with safety to the number of small boats and inexperienced persons frequent- 

 ing the river at this season of the year. It is, therefore, a consummation 

 much to be ilesired, that a subject so important to the welfare of this great 

 metropolis should receive the attention it deserves, and that the city autho- 

 rities, aided by government, will yet be able to carry into effect either their 

 former scheme of embanking the river to a more regular line, or some modi- 

 fication ijf this plan by which the present evils may be removed, so that this 

 noble river may again be restored to its former uselulness. 



OPE^fINGS OF RAILWAYS. 



The thirtieth of June witnessed a great extension of the Great Western 

 Railway, as on that day the main line was opened from Chippenham to 



Bath, 13 miles, the Cheltenham and Great Western to Cirencester, and the 

 Bristol and Exeter from Bristol to Bridgewater, .S3 miles. Thus the Great 

 M'estern Railway is opened throughout IISJ- miles, and there is a continuous 

 line of railway communication from London to Bridgewater of 152 miles in 

 length. 



On the 5th of July 285 miles of the Brighton line were opened, being 

 from the Croydon Junction to Hayward's Heath, and 5 miles from Clayton 

 Tunnel to Brighton, a measure which augurs well for the successful opening 

 of the remainder. 



The extension of the Blackwal! railway to Feneburch Street was to take 

 place about the period of our publication, so that all the metropolitan rail- 

 ways would thus be complete at their London termini. 



the unfortunate accident to the Fareham tunnel on the Gosport branch of 

 the South Western Railway, has unfortunately delayed the opening of that 

 line, just when it was on the point of being examined by the Government 

 inspector. 



GREENWICH RAILWAY. 



Amounts < f the tenders delivered on the 6th ult. for the fourth contract 



for widening the Greenwich Railway from the Croydon Junction. 



Messrs. Lee .... 15.825 



Mr. Munday .... 15.990 



Messrs. Little . . . 16.189 



Mr. Grimsdell . . . 16.53fi 



Messrs. Ward ... . 16,698 



Mr. Bennett .... 16,920 



Messrs. Piper . . . 16-920 



Grissell & Peto . . 17.280 



., Baker . . - 17-440 



THE "PRINCESS ROYAL" STEAMER. 



This splendid vessel, which appears to surpass the speed of any other in 

 the north, is now running between Liverpool and Glasgow, and has made 

 several successful trips ; she performed a trip from Dublin to Liverpool in 9 

 hours, and another trip on the 9th ult. from Greenock to Liverpnol in 15i 

 hours, the quickest passage on record, the distance is 227| miles ; she carried 

 at the time 100 tons actual weight. Both the vessel and engines wire built 

 by Messrs. Tod & Macffregor of the Clyde Foundry. Glasgow, the former is 

 of the following dimensions, viz., 185 feet keel and 208 feet on deck. 28 feet 

 beam, and 17 feet hold above the flooring, draws when light 8 feet, and when 

 full 10 feet of water ; her register is 750 tuns (N.M.). She is entirely built 

 of iron, (there is not a single beam of wood,) very strong, and has a fine ap- 

 pearance in the water, her cabins are very richly and tastefully fitted up. 

 The vessel is propelled by two steeple or upright engines of 190 horse power 

 eac/i, or 380 together ; the power is applied direct to the crank. Diameter 

 of cylinders is 73 inches, length of stroke 6 ft. 3 in., performs 18 strokes per 

 minute when in good trim, and 17 strokes with from 100 to 120 tons of cargo, 

 diameter "of piddle-whcel over floats 29 feet length of float 7 ft. 9 in., and 

 breadth 28 inches, speed in still water 15 miles per hour. 



Launch of the Devastation War Steam- vessel —Ihe launch of this first-class 

 war steam-vessel took place at Woolwich, on Saturday, 3rd ult. Mr. Lang, 

 master shipwright, superintended the launch ; she was immediately after 

 hauled into the dock, opposite the blacksmith's workshop, wliere she will be 

 coppered, and will be afterwards taken into the basin to have her engines 

 fitted and made ready for sea. The Devastation is about 180 feet long, and 

 about 1,050 tons burden, old measurement, or about 1,000 tons burden ac- 

 cording to the new mode of calculation. 



Tht Cadogan Chain Pier, Chelsea.— K3x\ Cadogan, the lord of the manor, 

 has erected'a handsome and convenient pier for steam-boat passengers on a 

 novel construction, at an expense of between £3,000 and £4.000. This erec- 

 tion was constructed by Mr. Cul;itt, from ihe design and under the direction 

 of Mr. Handtord, the surveyor and architect of the manor. The pier is situ- 

 ated in the mall of Cheyne-walk, the most beautifnl part of Chelsea, and 

 forms one of the most interesting objects of the place. Shortly the pier will 

 be open to the public. 



Professor Wagner's Electro- Magvetic Engine. — The German journals publish 

 the following extract from a protocol drawn up by the Germanic Diet; — 

 " The Germanic confederation desiring to acquire, for the purpose of pub- 

 lishing for the public good, the secret by means of which citizen Philip Wag- 

 ner, of Frankfort, makes use i^f electro-magnetism as a moving force, Sill 

 secure to the said Wagner for the exclusive ])ossession of his secret the sum 

 (f 100.000 florins (£8.000 British), on condition that he cause an electro- 

 magnetic machine to be constructed at his own expense, and upon a suffi- 

 ciently large scale, to serve as a locomotive ; that a trial be made of this 

 machine, in order that the diet be assured of its efficacy ; and that M. Wag- 

 ner consented to abide by the dec sion of the Diet on that trial. The Diet 

 will wait for one month for M. Wagner to accept those conditions. 



Land-slip at Sidmouth.—A land-slip of considerable extent took place at 

 Sidmouth on the 11th ult.. about seven in the evening. It commenced about 

 half-past six by a rumbling noise, resemhliug a distant peal of thunder, and 

 at seven o'clock part of the Peak Hill was observed to glide towards the 

 ocean, carrying everything before it. and forming a rock or pillar out of the 

 sea (70 feet high and 175 icet in circumference), opposite to the town, and a 

 quarter of a mile from the shore. It is covered with fossils, and is of a hard 

 iron-like substance. So singular an occurrence has attracted the attention 

 of every ore in the town, and hundreds are flocking frjm the immediate 

 neighbourhood to gain a sight of its results. — Dorset Chronicle. 



The Dissolving Views at the Royal Pohjleehnic Institution.— Ihe directors of 

 thisscieiitific institution, ever seeking to combine amusement with instruction, 

 have recently added to their numerous attractions an entirely new series of 



