198 



GREENHOUSE AND WINDOW-GARDEN WORK 



Method for finding boiler capacity j or cast-iron pipe 



Table showmn how to Rct at the amount of 33i2-inch cast-iron pipe necessary to 

 heat KH'tniiouse to temperature wanted, when outside temperature is at zero, 

 Fahrenheit (Lord & Hurnham Co.) 



For lU"* Im'Iow zero, add 10 per cent. ; for 20° add 20 per cent., and so on. 

 For 70° to 7o° diviih' stjuare feet of jihiss and ecjuivalent by 1.8. 

 For (jii° to 70° divide .stiuare feet of jila.s.s and etiuivaient hy 2.28. 

 For 00° to 05° divide square feet of gla.ss and equivaU-nt l)y 2.62, 

 For 55° to 00° divide square feet of glass and equivalent by 3. 

 For 50° to 55° divide square feet of glass and equivalent by 3.46. 

 For 45° to 50° divide s(|uare feet of glass and equivalent by 4. 

 For 40° to 45° diviile .S(iuare feet of glass and equivalent by 4.67. 

 For 35° to 40° divide square feet of glass and equivalent by 5.5. 



For 2-inch work, use same table and same example and multiply the amount 

 of 3J»i-inch pipe obtained by 1.08. 



In proportioning gla.ss surface, all wall surface must be figured in ; about 5 

 feet of waJl equals 1 foot of glass. 



Customary temperatures in which plants are grown under glass 



Asparagus plumosus 

 Azalea, Indian .... 

 Bulbs (hyacinth, tulip, etc.) 



Carnation 



Calla 



Chrysanthemum .... 



Cineraria 



Cyclamen 



Ferns, as maiden hair 



Lily (Ea.ster) 



Lily of the valley (forcing) 



Palni.s. house 



Primulas 



Rose 



Smilax 



Stocks 



Sweet pea 



Violet 



Day 



Night 



Various Estimates and Recipes 



Percentage of rays of light reflected from glass roofs at various angles of 

 divergence from the perpendicular (Bouguer) 



1** 2.5 per cent 



10° 2.5 per cent 



20° 2.5 per cent 



30° 2.7 per cent 



40° 3.4 per cent 



5^ 5.7 per cent 



^^ 11.2 per cent 



7<>^ 22.2 per cent 



IJ^ 41.2 per cent 



°^ 54.3 per cent 



