n8 LANDSCAPE DESIGN 



partly from the incompleteness and incongruity which he perceives 

 when he knows the real facts, an incongruity made the more striking 

 by the previous false conclusion which he had drawn, and partly 

 from the sense of having been duped, of having been expected to accept 

 a poor thing for a good one. 



In certain other cases no intellectual displeasure follows the dis- 

 covery of the illusion. This is true where, for instance, forms supposed 

 to be square or circular have been distorted for their effect in perspec- 

 tive, or where what gives the effect of a continuous straight axis of de- 

 sign proves on closer inspection to be broken at a point where it is im- 

 possible to see both parts of the line at once.* Here, though the reality 

 is different from the appearance, it is no less good. In such cases as 

 this the discovery of the illusion may indeed be a source of added pleas- 

 ure to the observer, pleasure perhaps in his own cleverness in having 

 made the discovery, pleasure certainly in the cleverness of the designer 

 and the skill of his adaptation of means to ends to produce a good 

 effect apparently precluded by the circumstances. 



Illusions of One of the commonest attempts to make one material look like an- 



Matcrwl other in outdoor construction is the facing of a brick or other wall with 



cement stucco and the drawing of lines in this stucco to represent stone 

 joints. This is often at its worst when the lines are supposed to imi- 

 tate random rubble masonry, but it is usually bad because it is not a 

 successful imitation. If the lines be drawn so that they suggest a 

 reasonable stone-jointing and make a pleasant texture in scale with 

 the wall, they need not be bad, though something straightforward 

 would usually be better. Another way in which the effect of one 

 material is imitated in a different material is our method of construc- 

 tion now so frequently used, of building a wall of concrete blocks cast 

 in a mold so that their faces are supposed to resemble a rough-pointed 

 stone surface. This need not be bad, but it often is so, again because 

 the imitation is not successful ; the concrete often comes from the 

 mold with rounded edges not at all like those of a roughly cut stone, 

 and when only a few different molds are used the frequent repetition 

 of exactly the same supposedly accidental form of surface becomes 

 evident and absurd. 



* Cf. Isola Bella, mentioned on p. 120. 



