220 The N.Z. Journal of Science and Technology. [July 
standards for the various materials used; and if all the manufacturers 
would make a point of complying with these standards the results 
aimed at, efficiency and safety, would be secured and the danger would be 
reduced to a minimum. The foreign manufacturer is the greatest offender 
in this respect, although the Britisher is not wholly blameless, while we, 
the consumers, must take our share of the responsibility for purchasing and 
using such products, knowing full well that they are far below the standards, 
and in many cases hazardous. 
Shoddy wire is a constant source of trouble, and is at times very difficult 
to detect. Some of it is so bad that its poor quality is seen at the first glance, 
while some is so deceptive in appearance that only a proper test will 
disclose it. This latter class of wire will frequently give a good test when 
newly installed, and would be passed by an inspector, but with age its 
insulating-properties rapidly deteriorate and the fire hazard is increased. 
The contractor is not wholly to blame for using some of the brands of this 
type, because he has not the necessary apparatus, which is rather costly, 
for testing the wire, and he is usually content to accept the word of the 
manufacturer’s agent that it is up to the standard ; or he may be largely 
influenced by the label on the wire, which in too many cases is absolutely 
misleading. There seems to be only one practical way to combat the evil, 
and that is for the underwriters’ and supply-authorities’ inspectors to pass 
no installation unless the wire used has the maker’s name or brand, pre¬ 
viously approved, printed continuously on the tape surrounding the rubber 
insulation under the outer braiding. This system of branding wires was 
first adopted by the members of the Cable-makers' Association, and there 
is nothing whatever to prevent a non-member adopting the same course. 
That would enable any length of wire to be easily identified, and the system 
should be welcomed by any firm that is not ashamed to have its name 
associated with its products. If they are, then let us do without their goods. 
Since the outbreak of the Great War much shoddy stuff, including wires 
and cables, ceiling-roses, switches, and lamp-holders, has found its way 
into the Dominion, and the position has been accentuated by the restricted 
exports from the British factories. 
Electric wires should always be protected against mechanical injury, 
and for that purpose the best protection is to enclose the wires in enamelled 
screwed steel conduit. If the wiring is outside a building, such as under 
verandas, &c., or in situations where subject to steam or moisture, the 
conduit should be galvanized to prevent rusting. The conduits should be 
first installed complete, and the wires drawn through after. It is bad 
practice to thread the wire through the conduit and then screw up the 
latter, because the wires inside are twisted, with the result that the 
insulation is damaged, and the possible fire hazard again introduced. At 
all outlet-points—that is, the position for ceiling-roses, fitting, or switch— 
the conduit should terminate in a metal outlet-box having a vulcanite 
cover, and the wires passed out through two holes. A wooden block, 
recessed at the back, is screwed over the cover, and the ceiling-rose, fitting, 
or switch mounted thereon. It will thus be seen that the wires are 
protected right through in proper channels to the terminals of the fitting, 
and are perfectly safe. In the case of switches, elbows are frequently used 
in place of the metal box, and the end fitted with a wood or ebonite bush 
to prevent the wires chafing against the sharp edge of the metal elbow. 
If carried out by an experienced wireman the job can be made safe enough, 
but at times I find the bush is missing and the wires jammed between the 
