Book III. 



MUSHROOM-HOUSES. 



333 



ciently warmed by one fire in winter, it should not contain more than 10,000 cubic feet 

 of air. As mushrooms will not thrive without some light, and at all events require air, 

 it ought to have two or three windows or valves for these purposes. 



1695. The German mushroom-house (Jigs. 279, 280 & 281,) It is a common practice with 

 German gardeners to grow mushrooms on shelves, and in pots and boxes, placed behind 

 stages, or other dark parts of their forcing-houses otherwise unoccupied, (Dietrich's 

 Gartner's Lexicon ; Ranslebens Briejfe, &c. ) This practice was carried to Russia, 

 and from Russia was brought to England by Isaac Oldacre, who thus describes the sort 

 of house adapted for the German practice. " The outside walls (G, Hi. Jigs. 279, 280.) 

 should be eight and a half feet high, for four heights of beds, and six feet and a half for 

 three heights, and ten feet wide witliinside the walls ; this is the most convenient width, 

 as it admits of a set of shelves three feet and a half wide on each side ; and affords a 

 space through the middle of the house, three feet wide for a double flue and walk upon 

 it. The wall should be nine inches thick, and the length of the house as it may be 

 judged necessary. When the outside of the house is built, make a floor or ceiling over it 

 ''as high as the top of the outside walls) of boards one inch thick, and plaster it on the upper 

 side (e, e) with road-sand well wrought together, one inch thick (this will be found supe- 

 rior to lime), leaving square trunks (f) in the ceiling, nine inches in diameter, up the 

 middle of the house, at six feet distance from each other, with slides (s) under them, to 

 admit and take off air when necessary ; this being done, erect two single brick walls (v, v), 

 each five bricks high, at the distance of five feet and a half from the outside walls, to 

 hold up the sides of the floor-beds (a, a), and form one side of the air-flues (t u, tu), 

 leaving three feet up the middle (t xt) of the house for the flues. Upon these walls (v, ?>) 

 lay planks (t v) four and a half inches wide and three inches thick, in which to mortise 

 the standards (/ k) which support the shelves. These standards should be three inches 

 and a half square, and placed four feet six inches asunder, and fastened at the top (k, Jc), 

 through the ceiling. When the standards are set up, fix the cross bearers in, in), that 

 are to support the shelves (o, o), mortising one end of each into the standards (/), the 

 other into the walls (n). The first set of bearers should be two feet from the floor, and 

 each succeeding set two feet from that below it. Having thus fixed the uprights (t k), 

 and bearers (in), at such a height as the building will admit, proceed to form the shelves 

 (.), o) with boards an inch and a half thick, observing to place a board (d,d), eight inches 

 broad and one inch thick, in the front of each shelf, to support the front of the beds. 

 Fasten this board on the outside of the standards, that the width of the beds may not be 



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280 



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diminished. The shelves being complete, the next thing to be done is the construction of the 

 flue (P, Jig. 281.), which should commence at the end (L) of the house next to the door, 

 run parallel to the shelves the whole length of the house, and return back to the fire-place, 

 where the chimney (S) should be built, the sides of the flue inside to be the height 

 of four bricks, laid flat-ways, and six inches wide, which will make the widtli of the flues 

 fifteen inches from outside to outside, and leave a cavity (tu, Jigs. 279, 280.) on each 

 side, betwixt the flue and the walls that are under the shelves, and one (xy) up the middle, 

 betwixt the flues, two inches wide, to admit the heat into the house from the sides of the 

 flues. The middle cavity (xy) should be covered with tiles, leaving a space (h) of one 

 inch betwixt each tile, for the admission of the heat. The top of the flue, including the 

 covering, should not be higher than the brick walls that form the front of the floor-beds. 

 The reason why the sides of the flues are recommended to be built stronger than usual, 

 is, because they support the walk. The walk itself is formed by three rows of tiles, the 

 outside rows making the covering of the flues, and those of the centre row are what cover 

 the middle cavity (xy), as above mentioned ; the outside cavities (t u) of the flue are 

 left open, the tiles which are placed over the flues being laid so as not to cover these 



