§ 77. Lord HUGH CECIL
asked the President of the Board of Trade whether by the directions of the Board a lantern test has recently been substituted for a wool test in respect to colour-blindness; whether nearly 50 per cent. of cases of colour-blindness detected by the lantern test passed the wool test; whether the defects of the wool test were pointed out nearly twenty-five years ago by Dr. Edridge Green; and why the Board of Trade have so long preferred the advice of those who, advocated the wool test?
On 1st April last a lantern test was introduced and certain modifications were made in the wool test previously used for examining candidates. Of the failures in the first two months in which the new tests have been in force about 50 per cent. passed the modified wool test, but deficiency was detected by the lantern. The Holmgren wool test has been adversely criticised by Dr. Edridge Green for many years. In adopting the test in 1894 the Board of Trade acted on the advice of a very strong committee of the Royal Society, presided over by Lord Rayleigh. The lantern test was adopted on the recommendation of a Committee which I appointed in l910 to consider whether any alterations in the sight tests were required.