362 



THE CIVIL ENGINEER AND ARCHITECTS JOURNAL. 



[October, 



tcr, «itliout a cartoon to work from, iii four liours; the painter's liaud 

 trembling with apprehension for the success of his experiment, and incom- 

 petent from inexperience to do full justice to the means. It is a rough 

 sketch, in short, made without the boldness and firmness of pencilling that 

 certainty of purpose and mastery of hand alone can give. Yet the figure 

 stands out from the wall, solid inform, lively in colour, and brilliant in tone, 

 making the pictures beside it look poor, flat, and muddy in comparison ; its 

 flesh tints surpassing in ])urity the freshest oil painting. It has a majestic 

 presence, that seems to enlarge the space it occu))ics, and to give new radi- 

 ance to the light reflected from it ; hut while it thus fills the sense and ele- 

 vates the mind, it is not obtrusive. In describing the impression made by 

 this piece of fresco, our object is not to compliment Mr. Ilaydon, or to praise 

 'his design. \Ve do but record the effect produced upon us by the work ; 

 though the conception and style of the painter must have had their share in 

 producing this impression, we endeavoured to regard only the physical quali- 

 ties of the art. The large scale of the design and the breadth and simpHcity 

 of the painting, have unquestionably a material influence over the mind; but 

 these characteristics belong to all fresco, and constitute its chief recommen- 

 dations ; the greatness of the style powerfully aids the grandeur of the idea, 

 and the largeness and boldness of the handling inspire the painter with con- 

 genial vigour of execution, which the cartoon he works from would prevent 

 from ruuniug into exaggeration. As the tendency of high finish in cabinet 

 pictures is to contract the focus of the mind and cramp the execution, so 

 that of fresco is to enlarge the conception and expand the style. Fresco 

 painting is the school of greatness in j.ainting; it daunts and depresses only 

 the little mind ; it fires and elevates the noble and aspiring genius ; the artist 

 works with that grand gusto of which we hear so much and see so little. 

 Mr. Ilaydon tells us, and we can well believe, that there is a fascinatiou in 

 the very manner of painting which is inspiriting and stimulating to fresh 

 exertions ; and he now regrets not having followed the advice of Sir David 

 Wilkie twenty years ago, to apply himself to fresco. Any zealous artist 

 might easily make the experiment ; the same means of information are open 

 to all. The book authorities for the Italian method, we are told, are Vasari, 

 Armenini, and Cennini. Messrs. LatiUa, of London, Bell, of Manchester, 

 and Barker, of Bath, are the artists in this country whom Mr. Ilaydon con- 

 sulted ; Mr. Lane, of whom we spoke, is not, we believe, in England. The 

 method is simple ; chip off the outer surface of the plaster from a dry wall, 

 and substituse for it a coating of wet plaster, composed of two parts of river 

 sand and one of lime, well mixed together with water to a proper consisten- 

 cy ; this applied to the wall will remain suflnciently moist to work upon for 

 four hour ; no greater space should be plastered at once than can be covered 

 in that time. Every touch is indelible ; but it may be gone over again when 

 the plaster is moist. The pigments used are of the common kind, being 

 earths, and are dissolved in water ; the lime itself is white ; the difBculty is 

 to allow for the change of tint in drying. — Spectator. 



I 



REVIEVirS. 



Illmtrations of Arts and Manufactures. By Arthur Aikin, F.L.S., 

 F.G.S., &c., late Secretary to the Society of Arts. London : Van 

 Voorst, ISn. 



Arthur Aikin is the scion of a literary house prolific in respectable 

 names — we need only mention Dr. Aikin, Lucy Aikin, and Mrs. Bar- 

 bauld. For a long while he was, as Secretary of the .Society of Arts, 

 the friend and adviser of the majority of the mechanical world, and 

 well did he sustain his own position and the character of the insti- 

 tution. As a popular lecturer on subjects connected with the practi- 

 cal arts few could exceed him, for while he possessed the art of rivet- 

 ing the attention of his auditory, he was remarkable for a precision of 

 idea and expression, which, even without the aid of diagrams or en- 

 gravings, enabled him to give complete and correct ideas of most in- 

 tricate and complicated machinery. So well was this known to be 

 Mr. Aikin's characteristic, that Lord Brougham, himself no mean au- 

 thority, is reported to have recommended a friend to apply to Mr. 

 Aikin, as lie knew "no other man but he who could make a specifi- 

 cation without drawings." When Mr. Aikin retired from the post, 

 which lie had occupied so long, it was to the general regret, but still 

 we hoped that one who had led u life so active and useful as his has 

 been would not remain idle in his retirement, although he has well 

 earned repose. We feel pleasure, therefore, in welcoming this first 

 fruit of his retirement, which, as it is natural, is devoted to his ancient 

 pursuits and connected with his former haunts. It is, what it pur- 

 ports to be, illustrations of arts and manufactures; it may, indeed, be 

 considered as a manufacturing sketch or series of essays. The sub- 

 jects treated on are pottery, limestone and calcareous cements, gyp- 

 sum, furs, felt, bone, horn, &c., iron, engraving and paper. In their 

 original form these papers were delivered before the Society of Arts, 

 at their evening meetings, where we recollect the interest they ex- 

 cited ; their republication therefore is likely to prove valuable. 



From the article on ])0ttery we have, at another page, given long 

 extracts relative to brick-making, so that we cannot do better than 

 here to take up the subject of limestones and calcareous cements. 

 After tracing the origin of cement to brick -building countries, in the 

 use of bitumen in the plains of Babylon. Mr. Aikin proceeds to al- 

 lude to the improvements in its application which were made by other 

 nations. To the Romans, however, he justly awards the palm among 

 tlie ancients for their use of calcareous cements, on account of the 

 extent to which they applied it in hydraulic works. They had also 

 an advantage in discovering the use of puzzolana (vide C. E. & A. 

 Journal, Vol. IV. p. 300.)* In alluding to the monuments of the Ro- 

 mans in this country our author Siiys that the most ancient limestone 

 quarries in this part of the empire, and which continue in full activity, 

 were first opened by the Romans at Tadcaster, in Vorkshire, which, 

 in the Roman itineraries, is named Calcariae. In giving this praise to 

 the Romans, it is to the Gothic style that we must refer the great ex- 

 tension given to the use of cement, the intricacy and elaborateness of 

 its parts, its richness and multiplicity of ornament, not allowing the 

 use of large blocks of stone. Limestones, Mr. Aikin divides after the 

 usual arrangement into four classes. The first contains the pure lime- 

 stones, including white statuary marble (which is of no use for mortar), 

 white chalk, oolite, and gray limestone. In the second family are 

 placed the svvinestones and bituminous limestones, which are of value. 

 Magnesian limestones come next, and lastly limestones containing so 

 large a proportion of iron and clay as to enable them to form cements, 

 which have the property of becoming solid under water, and are for 

 this reason called water or hydraulic cements. (On this subject see 

 also M. Vicat, p. 3 of our present volume). Among these are gray 

 chalk, chalk mail or Dorking lime, found in large quantities at Dork- 

 ing, Merstham and Hailing; blue limestone, lying betweeen the lower 

 oolite and the new red sandstone running across the country from N.E. 

 to S.W. frdin Whitby to Lyme Regis, sending out a branch to Mon- 

 mouth and Glamorgan. The entire thickness of this deposit is 450 

 feet, and among its chief quarries are Watchet, Aberthaw, Barrow and 

 Bath. In the three former, according to Smeaton, the proportion of 

 iron and clay appears to be the same, or about II per cent., but in 

 the time of Barrow, according to that authority, 21'3, but according 

 to Mr. Marshall, 14. In the upper and lower beds of the lias for- 

 mation, and in all deposits of bluish slaty clay containing carbonate of 

 lime, are balls of a compressed globular figure, less clayey than the 

 slate marl, but less calcareous than the limestone. In the London 

 basin these balls in the blue clay are called septaria or cement stone. 

 They may be observed in the cliff's of London clay forming the eastern 

 coast of the Isle of Sheppey, and in the low clitf at Southend in Essex. 

 They were met with frequently in the cutting for the Highgate Rail- 

 way and Primrose Hill tunnel. Of late years these stones, bnrned 

 and reduced to powder, have been very extensively used under the 

 name of Roman cement, in all water building and other masonry re- 

 quiring particular care, with such success as to have entirely super- 

 seded the employment of puzzolana and terras. These two materials 

 should also be noticed ; tiie first comprehends a few calcareous sub- 

 stances, the essential ingredients of which appear to be oxide of iron 

 and burnt clay ; the latter is quarried at Andernach on the Rhine for 

 millstone, and the fragments are ground up in Holland, and mixed 

 with lias lime to form a cement lor dykes and other works of the 

 water-staat. In England, Rowley rag, a, basalt obtained from the 

 Rowley Hills in Warwickshire, and in composition similar to the An- 

 dernach stone has been used for the same purposes with good effect. 

 The Egyptians, as it will be seen under the head of Ancient Engineer- 

 ing, used black liasalt from Abyssinia, With regard to sand, the use 

 of ])it-sand is objected to unless previously cleaned by washing, but 

 sand having a vellow colour, caused by ochre, and having chalybeate 

 springs rising from out of it, will produce a cement of great hardness, 

 provided that it be used soon after it is dug. But limestone and sand 

 are not enough of themselves ; the limestone must be deprived of its 

 carbonic acid, and used as soon as possible, as it reabsorbs carbonic 

 acid from the ;itmosphere. When packed in close casks, lias lime 

 will keep good for a long time, and Smeaton's experience goes as far 

 as seven years, but in this case, the lime was previously reduced to 

 powder by slacking with water, and then was trodden down into the 

 casks. The lime having cold water poured upon it, becomes hydrate 

 of lime or slacked lime, and in this state and not that of pure lime, 

 enters into the composition of mortar. The proportion of sand in 

 mortar depends partly on the fineness or coarseness of the sand itself, 



* It was an ancient law in Rome says Pliny. Ibat after the ingredients of 

 mortar had been rubied together wilb a little water, the mass should be kept 

 in a covered pit for three years before being used ; and we are expressly in- 

 formed ihat buiklings erected during the operation of that law were not liable 

 lo cracks. 



