In 1915, however, it was from every point of view of the first importance to get the trade union embargo on women's labour removed; and when it was removed, instantly evidence began to pour in of the high productivity of women's work. It was almost ridiculous to watch the amazement of the ordinary man when he saw how rapidly women learned men's jobs, and how, by their patriotic zeal and entire innocence of the trade union practice of ca' canny, their output frequently exceeded, and exceeded largely, the output of men working the same machinery for the same number of hours. The first evidence which reached the public of the high efficiency of women's labour was contained in an article in the trade journal _The Engineer_ of August 20th, 1915, the following passage from which is here quoted: "There is a widespread idea that the only machines which women can work are automatic or semi-automatic tools with which it is impossible to make mistakes. This idea is being daily disproved in the factory to which we have referred above, where some most delicate operations, necessitating the exercise of great skill and high intelligence, are being performed. We need only mention one case, but it will appeal to every mechanical engineer. In a certain screwing operation it was customary before the employment of women to rough the thread out with the tool, and then to finish it off with taps. Some trouble having arisen owing to the wearing of the taps, the women of their own initiative did away with the second operation, and are now accurately chasing out the threads to gauge with the tool alone. This is work of which any mechanic might feel proud.... In fact, it may be stated with absolute truth that women have shown themselves perfectly capable of performing operations which have hitherto been exclusively carried out by men."