This section is from the book "A Treatise On Architecture And Building Construction Vol3: Stair Building, Ornamental Ironwork, Roofing, Sheet-Metal Work, Electric-Light Wiring And Bellwork", by The Colliery Engineer Co.. Also available from Amazon: A Treatise On Architecture And Building Construction.
69. For exterior and interior lamp posts and brackets, wrought scroll-and-leaf work lends itself most readily. There is no detail of house furnishings wherein wrought iron can be put to such effective use in decoration as in electric and gas fixtures. The necessary presence of the wire conduit or gas pipe forms the purely utilitarian element of the design, and is so easily disposed that the designer may devote nearly all of his energies to the perfection of the ornamental details and the grouping in the composition. It may be well also to remind the student that another consideration than the ironwork itself materially affects this style of design, and that is the forms of electric lamps and globes, with which the fixtures are to be furnished. Electric lamps may be obtained in all sizes and styles, from the large 300-candle-power strictly for commercial use to the small single and half candlepower globes used for decorative purposes. The latter are frequently mounted on the end of white-glass tubes blown in representation of wax candles, a number of which are grouped in one candelabrum or bracket, diffusing the soft unobtrusive glow of old-fashioned candle light, without the offensive grease, smoke, or smell. Again, these same diminutive lamps are enclosed in china globes representative of various flowers, such as the rose, lily, morning glory, etc., and the bracket which supports them is correspondingly designed to suggest the details of the foliated bush or vine.
70. The lamp in most common use is the 16-candle-power size, and Fig. 95 shows the simple arrangement of one of these globes at the end of a wrought-iron wall bracket. The design is extremely simple; the tube containing the wires extends in a curve from the wall to the lamp. Iron scrolls appear to emerge from the small foliated wall plate with the tube, and help support it on the outside, while the lamp is so set that its light will not cast a shadow of any part of the ornament of the fixture.
Fig. 96 shows a similar design, somewhat more ornate, though precisely the same in principle. The tube or conduit forms, as it protrudes from the leafwork, the main stem of a floral device, from which scrolls branch out at each side, and at the termination of which is the blossom consisting of a 16-can-dlepower lamp, surrounded by a calyx of wrought-iron leaves.
The essential points of difference between Figs. 95 and 96 lie in the fact that the former consists almost entirely of strap-iron scrolls, while the latter is primarily a foliated design the scrolls of which exist as a part of the floral composition, and are not, as in Fig. 95, the main scheme of the design. The long wall plate in Fig. 96 renders this bracket much stiffer than the former one, particularly as the scroll on the curve of the conduit tends to tie the wall plate and bracket in two places. The scrolls in Fig. 95 might serve a similar purpose, but not without impairing the effect of a single tube springing abruptly from the wall surface.
71. In Fig. 97 we have a combination bracket designed for both gas and electric light. Here the wall plate is much heavier, and though the general scheme of design is similar to the example shown in Fig. 96, the leaf and ornamental work is heavier, as is required by the presence of more electric lamps and a gas globe. The main tube or conduit contains both the electric wires and the gas pipe, and as it terminates in a spray of four lamps and one gas jet, it must appear sufficiently strong and well proportioned to carry these details successfully - hence the extra leafwork to give its body bulk and weight, together with the scrolls which appear to support it from above. Behind these is the wall plate which apparently carries the weight of all, and is therefore made bold and substantial in proportion to the work it has to do.
72. When gas and electric fixtures are designed for exterior situations, they are usually in the form of posts, though sometimes a wall bracket is desirable, and occasionally a pendant from an archway. Fig. 98 shows a form of lamp post, the design of which is suggestive of a giant candelabrum. The base and shaft of cast iron are octagonal in plan, and support the three spherical globes containing the electric lamps. The arms supporting the globes are simply designed with just a suggestion of foliated work in the details. The globe may be of opalescent or ground glass, in order to diffuse the light from the electric lamps within, of which there may be three or more to each globe, according to the illuminating requirements. This style of lamp post is frequently used as a luminant for the porch of a private residence, hotel, or club, but for street lighting where the arc light is used, a different form of post is required, owing both to the difference in the form of the lamp, and to the care attendant upon its maintenance. Fig. 99 shows the style of support suitable for the latter case. It is executed in cast iron, as was the design shown in the previous example, but owing to the difference of its purpose the entire character of the design has necessarily been altered.
In the first place, the post shown in Fig. 99 is much heavier and bulkier than the one in Fig. 98; as, being likely to receive somewhat rough usage from passing vehicles or careless draymen, it must not be so slender as to be easily broken. The upper portion is designed as a loop or wicket, in which the arc light hangs under a protective roof or hood. Thus we see that its exposed position requires the street lamp to be heavy and strong, and that the character of the light it carries determines the form of its top, while the maintenance of the arc light requires the two projecting rungs a against which the keeper may rest his ladder or upon which he may stand when he adjusts new carbons or cleans the globe and copperwork.
73. In Fig. 100 is shown a form of post for a gas lamp. The main shaft or post is of cast iron, on which the fretwork and scrollwork of wrought iron is secured with countersunk screws. The lantern at the top consists of glass plates mounted in a wrought-iron frame which is covered with a dome-shaped hood. This lantern encloses the gas jet or jets and protects the flame from the wind. The scrollwork of this design is so delicate that it is hardly suited for a much exposed position such as a street light, but for courtyards and lawns or for park walks it is admirable, combining delicacy and refinement of design with simplicity and economy of construction.
The lamp shown in Fig. 101 is an elaborate design in cast and wrought iron, suitable as a porch light or as one of a series of lights arranged in a courtyard. The main body is of cast iron, decorated and relieved with wrought-iron leaf-work, secured to the cast-iron standard with countersunk screws. The design is suggestive of an antique, standard, and torch; only, where the flame of the torch would have existed in ancient art, the globe and electric lamp are present here. The globe in this case would be of opal or ground glass, for reasons similar to those stated in connection with Fig. 98.
74. Bracket and gate lanterns of various forms are used on the entrance posts flanking a gate, or suspended over the gate by means of a scrollwork arch. Fig. 102 shows a bracket lamp, the body of which is sheet iron and glass. The pyramidal sheet-iron roof-or canopy, as it is sometimes called - is pierced by eight small ventilators and finished on top with a foliated finial. The scrollwork connecting the lantern to the wall is composed entirely of strap work, and is secured to the masonry by means of expansion bolts. Strength and simplicity are the fundamental principles to be looked out for in this class of work.
The gateway lanterns shown in Figs. 103 and 104 are made of a combination of cast, wrought, and sheet iron. The design shown in Fig. 103 is intended to be placed between the gate posts, and is provided with the bracket scrolls a to distribute and support the weight, with the scrolls b to brace the grille laterally, and with the scroll c to prevent any tendency towards a rotary movement. The iron arch in Fig. 104 is designed to rest on the top of the gate posts, and the scrolls a are so arranged at the foot of the arch that they prevent any lateral movement or tendency to revolve, the weight being better distributed and also a firmer hold being obtained, by extending the large scroll b.