THE LORRY AND HEADLIGHT GLARE.
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The Need for Illuminating Large Vehicles and Big Loads.
IN MOTORCAR circles, at the present time, there is considerable agitation as to the decisions which will ultimately be arrived at by the committee set up by the Minister of Transport to consider the question of dazzling headlights. The committee has issued an interim report in which it is stated that the evidence which has been heard, and the results of tests that have been carried out, strongly point to the following conclusions, viz.:—
." (1) No satisfactory practicable dimming device to avoid dazzle has yet been discovered. such devices which avoid dazzle to any appreciable extent unfortunately fail to give a safe driving light, . and also, of course cause an extremely large per
centage of loss of course, power.
"(2) Far too powerful headlights are in comparatively common use at the present time..
"(3 Pending the discovery of some satisfactory dimming device, a. maximum power light, sufficient to give a safe driving light, should be fixed, and the reflectors in the case of all lights should be 'United in size, varying in accordance with the power of the light."
The lorry is far oftener a sufferer than an offender in this matter of headlight glare, and any solution of the problem, would be hailed with relief by all lorry drivers.
It is, however, important that any regulations which may be issued, or any anti-dazzling devices which are adopted, shall not, by unduly restricting illumination, make the remedy worse than the disease.
In this connection, it is interesting to refer to the report of the American committee which has considered the matter.• The first recommendation of this committee is that
"No headlight should be permitted such that the reflected or beam-light is projected above a plane 42 ins. above the road and parallel to it measured 100 ft. ahead of the vehicle, . . Permitting light in the upper right-hand quadrant of the beam is still favoured by some, but the majority of your committee favour limiting the beam to the lower quadrants, particularly in districts having numerous curved roads, etc."
Last year the London "Safety First" Council, who have endorsed the recommendations of the American committee, made, amongst others, the following recommendations, viz. :—
"No portion of the beam of light shall fall outside a plane parallel to and 42 ins, above the roadway measured at a distance of 100 ft. from the vehicle."
From the extracts given from these recommendations it will be seen that there is a general disposition to limit the height above which the main beam of light from car headlamps must not rise, and to permit only a certain intensity of illumination—yet to be determined upon—above that level.
This is a very important point so far as the commercial vehicle is.concerned. While the height at which the driver of a lorry usually sits is such as to make it certain that any regulation or device, which prevents eye dazzle of the pedestrian or passenger car driver, will also free the lorry driver of this nuisance, it is by no means certain that sufficient illumination will, at the same time, be provided for the lorry which he drives.
At the present time the commercial motor is by far the bulkiest vehicle on the road, with the exception of the tramcar, and the nature of the loads it sometimes. carries often makes it essential that the driver of an approaching or overtaking vehicle shall have a full view, not only up to a 5 ft. level, but of the complete vehicle and its load. The intensity of the illumination need not be such as to create "dazzle," but it should be sufficient to enable other road users to discern the type of vehicle and load at a considerable distance ahead.
Let it not be forgotten that any modification of motorcar lighting arrangements which would result in •sufficient illumination of other road-using vehicles would inevitably result in a revival of unreasonable prejudice, especially against the.raotor lorry.