Tms work has been compiled, not with the view of super seding any of the works already published dealing with the architectural or geometrical side of the stone-cutter's art, but as a means of introducing the student of Masonry to the practical work of everyday life in the workshop and on the building. It has no pretensions to instruct skilled workmen, but is intended to initiate young beginners in the craft into the rules and principles of good masonry. It is the result of many years' attentive observation and practical experience, acquired by the Author first as an Operative stone-mason, and afterwards as a foreman mason, on some of our largest public buildings. All the cases commonly met with are worked out, and, when the general principles applying to these are understood, their extension to any unusual question which may occur should not be difficult. The student is assumed, however, to have some knowledge Of geometrical drawing and projection, which indeed is indispensable. Most of the examples given are from actual work. In further explanation of his aim in compiling the volume, the Author may be allowed to cite the subjoined extract from an address delivered a couple of years ago by Mr. J. H. Morton, President of the Northern Architectural Association.* Mr. Morton said that it must be allowed that no trade could be properly learned out of the workshop.