54 Sloan's Architectural Review and Builders' Journal. [July, illustration is quite perfect. I wish this manner of illustration could be more frequently resorted to. In heating, the primary and most es- sential point is, to keep the feet warmer than the head. We have as yet paid but little attention to this ; but it is really the very foundation of the subject of heat- ing ; and I think much attention ought to be given to the endeavor to modify the manner of constructing our build- ings, so as to secure this end, physiologi- cally so important. The proper distribution of the heat on the cold sides of the room, instead of in the centre, as is too often the case, is a point of much practical importance. I think it has been very fairly demon- strated that we cannot have a comfort- able, vigorous atmosphere in a room, where all the air is heated hotter than required for breathing. Therefore no furnace, steam, or even hot-water apparatus, can warm a room satisfactorily by being placed in a chamber outside of the room, warming a current of air passed over it, and in- troduced into said room ; but there must always be some direct radiation, from surfaces exposed directly in a room, and hotter than the required temperature thereof. But much care must be taken not to adopt the other extreme of depending exclusively on direct radiation without the proper supply of partially-warmed air. The combination of direct radia- tion and a circulation of warmed air is therefore the best. To fill hollow walls with warmed air is a splendid arrangement for giving off a mild radiant heat. If we could keep all exterior walls warmed to say about 98°, or the temper- ature of the body, and the floor the same, with extra heaters or radiators of some kind under the windows, to coun- teract the excessive cooling at that point, we should soon find that the vexed question of Ventilation would be more than two-thirds solved already. The doors and windows would then be left open more freely ; and the halls, stairways, and open fire-places, which are the great natural ventilators, would then act a valuable part in maintaining that general circulation, so important to supply all the inmates of a building with food for the lungs. More, and at greater length, anon. AMERICAN AND FOREIGN WOODS. BY GtEOKGE J. Henkels.* INTRODUCTION. THE semi-continents of America, and the adjacent islands, produce the best woods for all mechanical purposes, and the most beautiful for ornamental use ; and the whole civilized world de- pends on them for its principal supply. The softer woods, such as Pine, Spruce, Hemlock, Poplar, Ash, Cherry, Oak, Maple and Walnut, are indigenous to the whole of North America. The hard woods, such as Lignum-Vitse, Cocoa,
- Cabinet and Upholstery Warerooms, N. W. cor
Ebony, Rosewood, Satin-Wood, Ma- hogany, and numerous other varieties, unknown in the mechanic arts, (and which, so far as tested, are of but little use for any purpose,) are all found in South America and in the islands of St. Domingo, Cuba and Porto-Rico. In the States bordering on the Mexican Gulf, north of the Isthmus, there are some inferior varieties of the hard woods ; but, with the exception of what is called Mexican Mahogany, there is nothing of any importance to the rest of the world. ner Thirteenth and Chestnut streets, Philadelphia.
