Below are various excerpts copied from the early electrical journals or books on the subject on incandescent lighting. The purpose of this page is to document some of the early spring tension lamp holders that were designed for baseless lamps with looped terminals, also referred to as "hookeye" based bulbs.

US Patent No. 274,427: Edward Weston, Incandescent Lamp Holder Patented March 20th , 1883

 

The Telegraphic Journal and Electrical Review March 7th , 1885 A NEW LAMP HOLDER. We have received from Messrs. Harrison, Cox Walker & Co. a sample of a new holder for incandescence lamps, which has just been patented and is now manufactured by that firm. A great amount of ingenuity is being generally displayed amongst electrical engineers in designing lamp holders which are at once simple, elegant, and capable of making and preserving good electrical contact. The apparatus shown in the sketch appears to possess in the last important point considerable advantages over the bulk of such articles. Should, however, the lamp be at times subjected to any side movement when being handled, it might be expected that the platinum loops would break off; but this of course may be avoided by extra tenderness in manipulation. The patentees state that in nearly all lampholders hitherto made, the small hooks which pass through the terminal loops on incandescent lamps give rise to a very considerable amount of resistance and consequent loss of light, owing to the exceedingly minute point of actual contact between them. Cox Walker's new holder is so constructed as to make the best possible contact between the loops and the terminals in the holder; and, at the same time it provides an additional support for the lamps where considered desirable. The body of the holder is three-quarters of an inch square, with a deep groove across the middle, in which are fixed flat nipping springs or pieces of metal, to which the terminals are attached. The loops in the lamps are placed between the springs, and two milled-headed screws nip the springs together, and thus hold the loops by the sides perfectly tight, making the best possible electric contact. The wire supports are made in various sizes to suit requirements, and add considerably to the appearance of the holder. We may add that these articles possess another important advantage in the shape of cheapness.

 

Enginnering May 1st, 1885 Cox-Walker Lamp Holder

 

The Telegraphic Journal and Electrical Review March 7th , 1885 GRUNDY'S LAMP HOLDER. We have recently described and illustrated several forms of incandescent lamp holders which have been more or less in general use, and we now furnish our readers with an illustrated description of an apparatus which we are informed is fitted in the Royal Courts of Justice. Fig. 1 is the lamp holder as fitted at the Royal Courts. Fig. 2 is the same adapted to screw into an ordinary gas or other tube. Fig. 3 is the upper part of the holder, showing the electrical connections, which are identical in both cases. The insulating parts are different, in that, as the upper part of fig. 1 is fixed to its socket by a screw through the centre, there are two separate holes for the leads, while in fig. 2, as it has to be screwed into the pendant or bracket, both leads must come through one hole in the centre to prevent their being twisted. A is a gun metal nozzle, which is in use in the original fittings at the Law Courts, and for which these holders were first designed; this nozzle terminates the pendant, tubular or flexible. If flexible, the space of the tube is occupied by a fibre, or other insulating plug, with two holes for the wires. The leads pass through two holes in the part B, and are secured by the binding screws G, in fig. 3, thus ensuring a good contact between the leads and the parts, H, which extend up the sides of the part B as far as the groove, I. S is the screw which secures B to A. The plates, H, one on either side of B, now represent + and - of the circuit, and this part remains a portion of the electrolier or pendant. Part C is movable, and consists of an insulating block with two metal arms, D, D, spread out in a fan shape, so as to partially encircle the neck of the lamp, and terminating at the other extremity in a collar made to fit the groove, I, in part B; the lamp is connected to these arms by the block, E, being pinched between the two parts of E, E, which are split, by means of the screws, F, F, thus ensuring a perfect contact and great rigidity in the lamp. There is no danger of fusing either lamp lugs or holder contacts, as the lamp can be adjusted to the part C at leisure, and put up in one second when required. The lamp is first put up, and afterwards connected to the circuit by giving the part C a quarter of a turn, thus enabling the holder to be used as a switch wherever the lamp is within reach, and, when used for this purpose, a stop is added to prevent overturning the holder. The whole of the contacts are in sight, and if used in a damp place, or anywhere where oxidization can take place, they are easily cleaned; in fact, the rubbing of the surfaces together in switching on and off will have a cleaning effect on the contacts.

 

Minutes of Proceedings of the Institution of Civil Engineers, Vol. LXXIX 1885 Siemens lamp holder for Swan lamps, Harold's Glow Lamp Holder

 

US Patent No. 392,666: Theophilus Coad, Incandescent Lamp Socket 1888

 

The "Walsall" Lamp Holder, The Telegraphic Journal and Electrical Review November 16th, 1888