16 



The Weekly Florists' Review^ 



May 9, 1012. 



ITS USE IN GREENHOUSES. 



Durability Combined with Cheapness. 



The object of this talk is to indicate 

 by illustration and description one of 

 the newer but rapidly expanding appli- 

 cations of concrete, namely, in green- 

 house construction. It is only within 

 comparatively recent years that serious 

 attention has been paid by florists to 

 the advantages offered by concrete in 

 this class of building. 



With the rapid decrease of our tim- 

 ber supply, and the resulting increase 

 in the price of lumber, there has come 

 a necessary demand for a new building 

 material. The progressive florist has 

 hailed with delight the advent and 

 rapid rise of the use of the new build- 

 ing material — concrete — a manufactured 

 stone as durable as rock, stronger than 

 brick or rubble stone masonry, adapt- 

 able to practically any form of detail, 

 but more important than all these to 

 the florist is its ultimate cheapness for 

 construction purposes. 



Portland cement is a term applied to 

 the finely ground product resulting from 

 the burning together of various mate- 

 rials of proper chemical composition. It 

 is not called Portland cement because 

 it was first made in Portland, Me., or 

 in Portland, Ore., but because the En- 

 glishman who first made it thought 

 he detected a resemblance between the 

 material and a certain natural stone 

 known as Portland. 



The first cement mill in this country 

 was built by David O. Saylor, at Cop- 

 lay, Pa., in 1871. There were, January 

 1, 1912, about 100 cement manufactur- 

 ing companies throughout the United 

 States, whose total output for the year 

 1911 was approximately 78,000,000 bar- 

 rels. This gives you some idea as to 

 the great progress made in a few years. 



What Concrete Is. 



Concrete is the hardened, rock-like 

 product resulting from a mixture of 

 Portland cement, sand and gravel or 

 broken stone with water. Cement is 

 the material which binds the sand, 

 gravel or broken stone together, the 

 whole being referred to as concrete. 

 There are many brands of cement on 

 the market. Each manufacturer gives 

 his product a special brand name and 

 uses a trademark, which is printed on 

 the sacks in which the product is 

 packed. The terms cement and con- 

 crete, while frequently used inter- 

 changeably, are in no sense synonymous. 



Up to a few years ago lumber was 

 used exclusively in bench construction, 

 but with the constant increase in price, 

 some florists began to experiment with 

 concrete for greenhouse construction. 

 At first the application was to posts 

 only and, as no drawbacks to the con- 

 crete posts with a spread footing were 

 found, it became standard practice. 



An abstract of an Illustrated talk by S. A. 

 Jamieson, of the Universal Portland Cement Co.. 

 before the Chicago inorlsts' Club, May 2, 1912. 



Next came the monolithic bench, of 

 which there are such excellent examples 

 in use today. 



Poehlmann Bros. Co., Morton Grove, 

 111., first used a monolithic or one-stone 

 bench 250 feet long and five feet wide. 

 These benches have given excellent sat- 

 isfaction, but the illustrations herewith 

 are of a concrete bench of a later design 

 used by them. It is of sectional con- 

 struction and, for the purpose of being 

 photographed, the piece shown in the 

 larger picture was set up by three men 

 in ten minutes. In the background are 

 piles of concrete lumber from which the 

 benches are made. This lumber is cast 

 in a central plant and as no piece is 

 heavier than one man can lift, it is eas- 

 ily handled and hauled to place, and can 

 be erected by common labor. 



Dimensions of Members. 



The bench consists of 6-inch tapered 

 posts having 10-inch bases; cross beams 

 forty-nine inches long, six inches d^ep 

 and one and one-half inches thick, rest- 

 ing in slots in the posts; 2x4 stringers 

 six feet two and one-half inches long, 

 resting on the cross beams; side pieces 

 of "L" shape, six feet long by ten 

 inches high by one and one-quarter 

 inches thick, with an angle cast at the 

 bottom three and one-half inches wide, 

 forming the rest for the bottom slabs; 



end pieces of the same section as the 

 sides, and bench slabs fifty-three inches 

 long, nine and one-half inches wide and 

 one and one-eighth inches thick, resting 

 on the sides and also on the stringer 

 at the center. 



The bottom slabs lock the whole 

 structure together, so that it has all the 

 stability of a monolith and yet cannot 

 be cracked or injured by a settlement 

 or movement of any part. Each mem- 

 ber is carefully reinforced with both 

 chicken wire and several ^-inch 

 twisted square bars, except the string- 

 ers, which have ^^-inch bars only. 



This bench may be erected with any 

 number of sections, is readily moved 

 when changes become necessary, has 

 perfect drainage, cannot tip over, can- 

 not rot or rust, never requires repairs, 

 is economical and is a permanent asset 

 to any florist. 



The plant required for making the 

 concrete lumber consists of a batch 

 mixer, sill molds and a number of spe- 

 cial molds for the sides and ends, which 

 were made up by carpenters. 



The first cost of construction was two 

 and one-third times what it would have 

 been for lumber. But fifteen years 

 from now the concrete benches will be 

 as good as they are today, while in the 

 same period three sets of wood benches 

 would have been built at a greater cost 

 than for concrete. The actual economy 

 of concrete is thus demonstrated con- 

 clusively. 



Poebltnann Sectional Concrete Bench Just After Planting: to Roses. 



