Mr. Badoureau further says that "while as an engraver he has so high an opinion of the qualities of compressed wood as a substitute for boxwood, as the inventor of the new process he considered that it possesses numerous advantages both for artistic and industrial purposes." In short, he says, "My wood is to other wood what steel is to iron." The following woods are those which have, from time to time, been proposed or experimented upon as substitutes for boxwood, for engraving purposes. They are arranged according to their scientific classification in the natural orders to which they belong: _Natural Order Pittosporeae_. 1. _Pittosporum undulatum_. Vent.--A tree growing in favorable situations to a height of forty or even sixty feet, and is a native of New South Wales and Victoria. It furnishes a light, even grained wood, which attracted some attention at the International Exhibition in 1862; blocks were prepared from it, and submitted to Prof. De la Motte, of King's College, who reported as follows: "I consider this wood well adapted to certain kinds of wood engraving. It is not equal to Turkey box, but it is superior to that generally used for posters, and I have no doubt that it would answer for the rollers of mangles and wringing machines." Mr. W.G. Smith, in a report in the _Gardeners' Chronicle_ for July 26, 1873, p. 1017, on some foreign woods which I submitted to him for trial, says that the wood of _Pittosporum undulatum_ is suitable only for bold outlines; compared with box, it is soft and tough, and requires more force to cut than box. The toughness of the wood causes the tools to drag back, so that great care is required in cutting to prevent the lines clipping. The average diameter of the wood is from 18 to 30 inches. 2. _Pittosporum bicolor_, Hook.--A closely allied species, sometimes forty feet high, native of New South Wales and Tasmania. This wood is stated to be decidedly superior to the last named. 3. _Bursaria spinosa_, Cav.--A tree about forty feet high, native of North, South, and West Australia, Queensland, New South Wales, Victoria, and Tasmania, in which island it is known as boxwood. It has been reported upon as being equal to common or inferior box, and with further trials might be found suitable for common subjects; it has the disadvantage, however, of blunting the edges and points of the tools. _Natural Order Meliaceae_. 4. _Swietenia mahagoni_, L. (mahogany).--A large timber tree of Honduras, Cuba, Central America, and Mexico. It is one of the most valuable of furniture woods, but for engraving purposes it is but of little value, nevertheless it has been used for large, coarse subjects. Spanish mahogany is the kind which has been so used. _Natural Order Ilicineae_.