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the produce tends to become mangled. The points mentioned particularly a^out 

 the above houses are labor savers and have been well considered before they 

 were adopted. Men who have to drive their produce to market have found 

 out that lettuce loaded in a fairly warm room and securely covered has a better 

 selling value than lettuce carried out into the frosty air to be loaded. Little 

 points like these are what are making money for these men in the greenhouse 

 business on the other side and some might well be copied here. 



GLASS AND GLAZING. 



Too much importance cannot be given by the builder to these points. The 

 outside surface of the greenhouse is that which receives the direct blows, and 

 it must be strong enough to withstand the severest storms. 



There are many grades of glass on the market which have been sold as 

 suitable for greenhouse building. Ordinary window glass will not do; a stronger 

 grade is necessary. A heavier grade of glass is used for greenhouses. The glass 

 should be carefully gone over and all lights having flaws or whorls in them 

 should be discarded. Burning of the crops underneath will result from the 

 strength of the sun's rays. Another point which should be remembered here is 

 that of evenness of edge. This is absolutely necessary where success is expected 

 with butted glass. 



Sizes 16 by 24 inch glass is the most popular size in the U. S., while many 

 growers use even a larger size. Some using as large as 20 by 30 in districts where 

 there is litle danger from hail or from very severe wind storms. 16 by 24 is 

 used in different ways laying it the 16 inch way and the 24 inch way, thus 

 placing the sash bars 16 inches apart and 24 inches apart. Some growers claim 

 that there is considerably less breakage when the bars are laid to hold the 16 inch 

 glass. In other sections it seems to be the rule to use glass the same width as 

 above, but 12 inches in length. This still gives the bars 16 inches apart, but 

 makes the joints come just twice as many as with the 16 by 24 inch glass. This 

 method uses the same amount of supports, but is not in favor by the majority 

 of growers owing to the fact that there are such a number of joints or laps 

 whichever the case may be. Growers prefer the 16 by 24 inch glass, and take the 

 chance of heavy breakage bills. In Ontario, glass 20 by 20 inches in size is the 

 most popular among those having plants of any size. This gives a good light, and 

 is convenient for use with bar and cap, which is the common method of putting 

 on the glass in Ontario houses. Owing to the square there is double the Chance 

 of securing a tight fitting joint, as the four sides of the glass may be fitted. 

 This is a good size of glass to use, giving plenty of light, and being not too 

 large so as to increase the breakage cost; 16 by 16 inch glass can also be used 

 and for the same reasons. It is not advisable to use glass of a larger size than 

 16 by 24 in Ontario, and most growers will not chance that size, preferring to 

 take a little more shade but lessening the repairs and using either 16 by 16 or 

 20 by 20. 



Butted oe Lapped Glass. — Butted glass is commonly to be found on green- 

 houses in Ontario, and means that the sash bar is so constructed as to allow the 

 glass to be laid on, one light butting against the next one up, and then a wooden 

 strip which fits on to the bar is screwed on, and this holds down the side of 

 the glass. 



