A UTOMA TIC GREEN HO USES. 



6ii 



was made like the walls, with felt lining, and was 

 hung with a tight-fitting joint. The building was 

 practically a refrigerator, and was designed to be, 

 like the large refrigerators in meat stores; as nearly 

 air-tight as possible, and, unlike a refrigerator, to 

 keep cold out instead of keeping heat out. 



The building measured i8 feet (6 sash) over all 

 on top. The rear wall was 6.} feet high on the out- 

 side and 5?, feet inside. The front wall was 3 feet 

 3 inches high on the outside. The sash were 6 feet 

 long, which gave, with the proper slope, a clear 

 space inside of 5 feet 8 inches. The interior length 

 was about 17 feet. The cellar being 18 inches deep 

 gave ample head room at the rear. The table ex- 

 tended across the west end and was 15 feet long, 

 giving a table surface of 51 square feet, and shelv- 

 ing at the back and ends gave a total of 74 square 

 feet of available space for plants. Rhubarb was 

 also cultivated under the table. 



It will be observed that no means are provided 

 for raising the sash to secure ventilation. To per- 

 mit the warm air to escape and to exclude cold 

 drafts, four lights of glass were taken out at the 

 upper end of one sash near the middle of the house. 

 This gave four openings, 8x10 inches, 320 square 

 inches. On these openings was placed a wooden 

 box or trunk, 12 inches high at the back and with a 

 flat roof or hood. In the center of this trunk was 

 cut a round opening 12 inches in diameter, and over 

 this was placed a sheet-metal chimney, having a 

 cap or hood at the top, the chimney being 18 inches 

 high. Within the trunk was a 

 valve carefully balanced in the 

 middle and fitting tight when 

 closed. Figure 3 gives a section 

 showing the ventilating trunk, 

 chimney and valve in position 

 on top of the sash. The trunk 

 was three feet long and 1 5 inches 

 wide. 



It will be seen that this sys- 

 tem of ventilating keeps out all 

 back drafts or cold winds that, 

 by the usual method of ventilat- 

 ing, are sure to blow down on 

 the plants. Experience with 

 this ventilator in actual opera- 

 tion over several months, in- 

 cluding cold, windy days i n Section of Ventila- 



March with hot sunshine, shows tor Chimney, Cap 



AND Valve. 



that it was ample to keep the 

 house at any required temperature. The actual 

 outlet for the hot air was only 12 inches in diameter, 

 but it was sufficient, because the valve began to 



open the instant the heat began to accumulate. 

 Being automatic, there was no delay waiting for 

 some one to open the house, and the instant the 

 temperature rose above a certain point (say 80°) the 

 valve began to open, and as soon as it was open, 

 even a quarter of an inch, the hot air began to go 

 out. In like manner the moment the temperature 

 began to fall the valve began to close. Even a 

 cloud passing over the sun caused the valve to move, 

 and if the cloud remained more than a few moments, 

 the valve would completely close, thus cutting 

 off the waste heat. The manner of operating the 

 valve was very simple. A large thermostat was 

 hung on the under side of the sash and connected 

 by balanced rods and bell-joints with the valve. 

 The actual movement of the rod of the thermostat 

 was only one fourth of an inch, while the complete 

 movement of the valve was over three inches. By 

 the use of suitable bell-joints and rods, it was not 

 difficult to adjust the valve to the thermostat so that 

 they would move together automatically under the 

 heat of the sun shining through the glass. 



Next in importance is the peculiar heating system 

 invented by Mr. Barnard. It is not a new idea to put 

 an oil stove in a small plant house. The novel feat- 

 ure was the placing of a hot-water boiler on top of a 

 common two-wick oil stove, and using the boiler to 

 heat hot-water pipes. Even this idea would not be 

 of value were not another idea supplemented to it. 

 This is to utilize the heat of radiation from the 

 stove, and at the same time to get rid of products 

 of combustion. To do this the boiler was enclosed 

 in a sheet-metal casing, and from the top of the 

 casing a small chimney extended through the roof. 

 By this arrangement nearly all the heat was ex- 

 tracted from the stove without allowing any of the 

 smoke or gas to enter the building. The boiler was 

 made of sheet zinc, and was 27 inches long and six 

 inches in diameter. In the boiler were set four 

 tubes made of one-inch gas pipe, thus making a 

 tubular boiler. At one side, close to the bottom, 

 was fitted a one-inch pipe, and another was fitted to 

 the top near the center. Figure 4 shows the boiler 

 and connections. On each pipe were placed union 

 couplings, and to connect the pipes with the two- 

 inch hot-water circulating pipes reducing joints were 

 used, as shown in Figure 4. In the figure, dotted 

 lines show one of the flues in the boiler and the 

 positions of the others are indicated at the bottom. 

 A water-cock on the boiler is also shown. The up- 

 per pipe is the "flow," and the lower pipe passing 

 down the side of the boiler to the bottom is the " re- 

 turn." The circulating pipes extend along the 

 front of the house and across the end to an ex- 



