But it was astonishing how, feeling greater confidence in the handling of their machines, airmen began to join issue with this enemy the wind. They were helped, too, by a growing efficiency in the construction of their craft. Machines were built more strongly, engines were more staunchly made; in all details that spelt reliability, were aircraft improved. But the wind, none the less, took its toll. It was not combated without loss of life; and we find that, before the end of 1910, nearly thirty men had been killed while flying. In many cases, struck by a heavy gust, a machine collapsed in flight; in others, beaten over by the force of the wind, but with his craft intact, the pilot had fallen to earth, powerless to regain the control of his machine. [Illustration: PLATE IX.--THE FIRST HIGH-POWERED BLERIOT. This type of monoplane, in which Mr. Grahame-White learned to fly--being seen with a passenger above--was built by Bleriot for the speed contests at Rheims in 1909. It had an 80-h.p. motor, as compared with the 25-h.p. engine which was then fitted to ordinary Bleriots, and attained a speed of 60 miles an hour.] In wind-flying there were these two distinct dangers: a man might be dashed to earth by a gust when rising or descending; or he might be struck by a rush of wind when at a considerable height, and find his craft driven over until it began to slip sideways instead of flying forward. In “side-slips,” as they are called, there lies a grave risk. What happens is this. A man flying in a wind may, by vigorous use of his ailerons, recover the balance of his machine time after time; but as the wind rises, he may be struck ultimately by a gust that tilts his planes to an abnormal angle, despite his efforts to check them. The machine will then heel till it stands almost vertical--till it reaches such an angle, in fact, that it ceases to move forward and begins to slip sideways--skidding away, beyond the pilot’s control, like a motor on a greasy road. How an abnormal gust may cause a side-slip is illustrated by Fig. 53. [Illustration: IN NORMAL FLIGHT. FIG. 53.--Machine “side-slipping” in a gust. STRUCK BY AN ABNORMAL GUST. MACHINE SLIPPING SIDEWAYS.]