ual number (in some jobs plain rectangular pieces, known as "ashlar," are not numbered individually). A tender, known as a derrickman, locates the pieces to be needed and brings them to the mason. If sufficiently large and heavy, they are set in place by a derrick or crane, but most pieces are picked up and set by hand. The mason prepares a mortar bed, places the stone in the bed, and taps it into position as needed with a wooden mallet until it is in proper alignment. Because of the expense, a wall of solid cut stone is exceedingly rare; usually the stone is mainly a rather thin covering on the exposed surface or surfaces, with brick or other less expensive materials used for the remainder of the wall thickness. Sometimes the bricks are laid by the stonemasons, but, in cities large enough for the distinction between bricklaying and stonemasonry to be observed, they are put in place by bricklayers. Stonemasonry is much more exacting than brickwork in the details of appearance. Surfaces, edges, and mortar joints are much more easily seen and are viewed much more critically; hence, it is necessary that alignment be maintained much more accurately, that joints be uniform, and that minor chipping of the corners be avoided.

Rubble stone work was an important structural material until superseded by concrete but is now used only for appearance in some houses and other buildings and in some places. for a few minor uses, such as low retaining walls at the edge of steeply banked lawns. It uses rough stone, which the mason cuts (breaks) to size as he lays it. He lays the pieces. in a bed of mortar but does not maintain uniform horizontal courses or vertical joints such as are used for brickwork. Pieces can be cut and fitted rapidly in this manner by a skilled man, but it is still handwork and correspondingly expensive; hence, this type of work is

uncommon.

Training is through apprenticeship which in some features is similar to that for bricklaying. There are also combination apprenticeships preparing for both brickwork and stonework, in localities where there is not enough stonework for reasonably steady employment.

Outlook

It seems very likely that stonemasonry will continue in use permanently, but there are strong indications that it will be used less extensively than in the past. The trend toward simpler lines means less stone ornamentation and less extensive use of moldings and other pieces than plain ashlar. The trend is also toward larger window areas in some kinds of buildings, with less exterior wall area. Gothic is no longer the unchallenged first choice in university architecture. Changed architectural preferences have also appeared in church buildings, and there are some indications that a similar change will come in public buildings within the fairly near future, although perhaps not immediately.

These considerations mean likelihood of a gradual decline in employment. This will probably be slow enough so that it will not threaten present members of the trade, especially since. average age is high, and new workers will certainly be needed; but, since this is both a small trade and a contracting trade, the apprenticeship opportunities are limited.

Chicago, Ill.

Cleveland, Ohio

Denver, Colo.

Area

Jackson, Miss.

Kansas City, Mo.

rate

2.25

2.25

2.50 2.622

2.20

Little Rock, Ark.

Los Angeles, Calif.

Louisville, Ky.

2.50

Milwaukee, Wis.

Minneapolis, Minn.

2.25

The principal work of this trade is the finishing of the exposed surface of concrete work, with any pitch wanted for water drainage, etc. Other work includes patching the surface of structural concrete after the forms have been removed, laying of mastic floors, and laying of composition (magnesium cement) floors.

Finishing of concrete floors and other concrete members is the most important source of employment. This work is done on sidewalks, driveways, curbs, roofs, stairs, and many other structures or structural members, as well as floors. Pouring of concrete which is to have a trowel-finished surface sometimes proceeds. in two stages-first the main mass of material containing gravel or other coarse aggregate, which is leveled off about one-half inch below the final surface, and then a top coating of finer material without gravel, which is spread onto the coarser concrete below. In such cases, it is mainly this fine mixture with which

there is no separate top coating, and the finishers deal with the surface of the main mass of concrete. In either case they spread the material to about the level desired by means of a straightedge, guided by strips which they have set to indicate the proper surface, and then trowel it a number of times at different stages of hardening. Often a level surface is wanted, and in other cases a slope is wanted for water drainage toward the floor drains in a garage floor, toward one or more sides of a concrete roof slab, etc. Provision for this slope is made in final grading of the ground (for a slab resting on the earth) or in building of the forms, and in pouring of the rough concrete, but it is the finisher's job to produce a final top surface conforming to that desired. Finishing of curved rather than approximately flat surfaces (street curbs, curbs at the edge of driveways, etc.) is done in a generally similar manner. More similar to plastering (particularly stucco work) is the job of applying an outer covering of fine material to retaining walls and other vertical surfaces. This is done after the forms have been removed, a few days after the main mass of concrete has been poured.

The patching work occurs mainly in concreteframe buildings and is done to correct surface defects which are exposed when the forms are removed. Fins protruding where joints in the forms were too wide are chipped off and ground with an abrasive; "honeycomb" areas, where there had been insufficient spading during placing of the concrete, are cleaned, with any loose material removed, and are filled with a cementsand mixture; and similar minor corrections are made for the purpose of improving the appearance of concrete which is to be exposed in a completed building.

Mastic floors are a layer of fine asphalt mixture, quite like that used for the top surface of street paving, and are usually laid over concrete. They are used where resistance to acid is necessary mainly in dairies, ice cream plants, breweries, and other factories in the food-products industry. The material is applied hot and is smoothed with heavy hand tools.

Composition floors are thin layers made with a type of magnesium cement laid over a rigid base. The operations involved are very similar

fied by differences in the characteristics of the material. At one time these were popular for small commercial buildings, but now they are used mainly for deck surfaces and similar uses in shipbuilding.

Finishing of newly poured concrete usually involves overtime work, frequently quite extensive overtime, because of the characteristics of the materials. On better-grade jobs, where high standards of workmanship prevail, the finishing operation continues to a final troweling when the fine material is fairly rigid, and this is several hours after it has been poured. The setting time depends on the temperature and the type of cement used but is fairly lengthy in any case. For re-enforced floors in buildings, very often pouring is continued until after the normal quitting time in order to reach boundaries where a break in the concrete will not introduce structural weakness; this means that the cement finishers often do not complete their work before 10 and may work until midnight or later. Such hours bring high daily and weekly earnings when they occur, but they are offset by intermittent employment, because it is exceedingly uncommon for pouring of build-· ing concrete to go on day after day; ordinarily one or a few days of pouring are followed by days of building forms, setting re-enforcing steel, and making other preparations for the next pour. Sidewalk and driveway work is more regular, because many of the contractors for such work are able to obtain a continuous series of moderately small jobs, but on this work the overtime is usually less. The jobs are smaller, there is seldom the engineering necessity for pouring until a suitable boundary is reached, and pouring often stops earlier in the day. The finishing specifications are also less exacting in many cases, so that troweling can be stopped at an earlier stage of setting. In small localities, many journeymen are both cement finishers and plasterers, and in such places there is apprenticeship for the two trades combined.

Where Employed

Cement finishers are employed predominantly in the construction industry. Some work for "cement contractors" doing mainly small jobs

walls, basement and garage floors, etc.; these men work fairly regularly, except that the volume of employment is low in winter, and outdoor work is postponed for rain. Some work for city paving contractors, mainly on street curbing; this employment is rather similar to that for "cement contractors." Some work for general building contractors or for re-enforced concrete contractors on finishing of floor slabs and roof slabs in concrete-frame and steelframe buildings. There are numerous other jobs-on bridges, abutments, and most structures where concrete is used. The early concrete highways were finished by hand, but finishing machines have been used for a number of years; hand-finishing of highways is confined mainly to curves and irregular areas outside the range for which the finishing machine rails are set up, although on most concrete paving crews there are cement finishers to perform smoothing operations supplementary to that of the finishing machine. Mastic floors are laid mainly by finishers specializing in such work, who move to successive jobs over a quite wide area; the same is true of composition floors.

Government units (municipal public works departments particularly), particularly), utilities, some manufacturing firms, and a certain number of miscellaneous establishments also hire cement

finishers.

Outlook

The employment outlook at the present time is very good, and it should continue to be good for a number of years, because this is likely to be an expanding trade. Use of concrete in building construction has increased and seems likely to increase further. A comparatively few years ago re-enforced concrete construction was almost unknown for apartment buildings below luxury grade, but it has become moderately common in investment housing projects as well as in public housing. Houses without basements, with a concrete floor slab laid on the ground, have come into use, and have been stimulated by their suitability for panel ("radiant") heating. Other uses have also developed or grown, and further development is very likely.

total volume of employment, but not for a change in its basic characteristics. Nothing evident to date indicates likelihood of substantially improved regularity of employment or an evening out of the alternation in concrete frame buildings between days with extreme overtime and days of lay-off.

While finishing machines are highly satisfactory for paving work, the vastly different conditions for other types of poured-in-place concrete make the use of similar machines unlikely. Small machines for finishing floors, etc., have been used for several years and have proved valuable on flat surfaces. These consist of an electrically rotated blade covering an area about 3 feet in diameter which is moved over the floor by the cement finisher.

For additional information, or for the address of the union local nearest you, write to the Operative Plasterers' and Cement Finishers International Association, 200 Fidelity Building, Cleveland 14, Ohio; or the Bricklayers, Masons, and Plasterer's International Union of America, 815 Fifteenth Street, NW., Washington 5, D. C. Information may also be obtained from the Apprenticeship Committee of the Associated General Contractors, 1227 Munsey Building, Washington 4, D. C.

Structural and Ornamental Iron Workers Outlook Summary

Opportunities are good for at least the next several years for those who want to enter as apprentices. The field for ornamental metal work has increased noticeably within the last two decades, and further increase seems very likely.

Nature of Work

Structural iron workers erect the steel framework for buildings. Best known are the tall buildings common in downtown locations, but structural-steel columns and roof framing are used frequently in one-story factory buildings and to some extent in other types of buildings. Factories may also require steelwork for crane runways and to support heavy equipment. The men in this trade also put up steel bridges and towers and install or erect certain types of tanks. They install steel floor decking, which has become popular for office buildings and other buildings having light floor loads. In some cases they set structural-steel members in place when they occur in buildings not of steel frame design, such as beams over wide doors and windows in masonry walls to support the brickwork above. Structural iron workers erect steel scaffolding and sidewalk canopies for use by other construction trades and for protection of the public, both for new buildings and repair work. The steel scaffolding for exterior repairs to a tall building can be a fairly large job in itself. Other work includes the placing of vault doors with their frames and installing the steel plate work covering the exterior of burglar-resistive vaults. Struc

machinery, equipment, etc.), except in those localities where rigging is treated as a separate occupation.

In erecting a steel framework or structure, the structural iron workers first take the steel shapes already fabricated by other workers and hoist them into place in the proper order. They then connect them temporarily with bolts, accurately align the structure as necessary, and rivet or weld the parts together.

Ornamental iron workers typically handle lighter materials, such as those not making up the basic framework of a building. The name "ornamental iron" is historical and is likely to be misleading. Within recent years a large part of the work, probably more than half, has dealt with other metals than iron and steelmainly aluminum alloys, brass, and bronze. In some cases the installations are highly decorative, although along much simpler lines than 20 or 30 years ago, while other installations are strictly utilitarian.

Ornamental iron workers install metal stairways (which are much commoner than they seem, because the treads and platforms are commonly filled with concrete) and the railings and handrails at stairways, balconies, and elsewhere. They install metal floor-gratings, catwalks, and ladders, used extensively in powerhouses and a few types of factories. They put in place solid metal sash and doors and their frames, including the common steel sash used in many kinds of buildings; swinging and revolving metal doors with their frames; and vestibules at the street entrances to office buildings, hotels, etc. Other work done includes doors, grilles, and screens, such as used at bank tellers' compartments and elsewhere; gratings; metal cabinets of many types, such as display cases and safety deposit boxes; window and door guards; and a very wide variety of other installations.

Where Employed

Structural and ornamental iron workers are engaged largely on new construction. They are also employed on alteration work, such as insertion of a mezzanine floor in steel-frame buildings; installation of steel stairs, during modernization of an old apartment or commer

to an existing building for burglary protection. There is even a little repair work, despite the durability of the materials - replacement of members weakened by long neglect of painting, replacement of bridge parts damaged by bad traffic accidents, etc.

The structural workers do no fabrication of their materials beyond reaming out of mispunched rivet holes and other small corrections of shop errors. In general the ornamental workers likewise do no fabrication, although some of the smallest contractors (especially in small communities) do not distinguish sharply between shop crews and field crews. Occasionally, larger contractors use some of their erecting crews for shop work to handle peak loads, but this practice is not prevalent because of the substantially higher wage scale for the erecting men.

Ornamental iron workers are commonly employed within commuting distance of home because establishments capable of doing a wide variety of work can be maintained on a fairly low volume of business and hence are found in many localities. Ornamental metal for an occasional elaborate building in a small city is likely to be provided by a contractor from a larger city, who ordinarily either sends his own crew or sends a partial crew and hires other workers locally.

On the whole, more traveling is involved for structural iron workers, because most localities have insufficient structural business to support an erection contractor or local crew. Consequently, workers must be brought in from outside to handle the occasional structural work that occurs, such as a steel-frame office or factory building. Workers living in the largest metropolitan centers and preferring employment there are likely at times to find that the only vacancies are for out-of-town jobs.

Training and Qualifications

The standard apprenticeship period is 2 years, with provision for another 6 months of training if necessary. Men with several years. of experience as helpers sometimes become journeymen, but, as the trade is highly unionized, few enter without serving a formal apprenticeship.