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slenderer, when the flutes of the external columns hetwenty-four in number, these may have twenty-eight, oreven thirty-two. Thus, what is taken from the absolutemass of the shaft, will be imperceptibly aided by thenumber of the flutes, and though of different thicknesses,they will have the appearance of being equal. This arisesfrom the eye embracing a greater number of surfaces,and thence producing on the mind the effect of a largerbody. For if two columns, equally thick, one of themwithout flutes, and the other fluted, are measured roundwith lines, and the line is passed over the flutes andtheir fillets, though the columns are of equal thickness,the lines which girt them will not be equal, for thatwhich passes over the fillets and flutes will of course bethe longest. This being the case, it is not improper inconfined and enclosed situations to make the columns ofslenderer proportions, when we have the adoption ofthe flutes to assist us. The thickness of the walls of thecell must depend on the magnitude of the work, takingcare, however, that the antse are the same thickness asthe columns. If built in the ordinary way, they are tobe of small stones, very carefully laid, but if of squarestone or marble the pieces should be chiefly small andof equal size, because then, the upper stones comingover the middle of the joint below them, bind the worktogether and give it strength; fillets of lime used inpointing the joints and beds give the work an agreeableappearance.