Table:
text: List of Snaefell Mountain Course fatal accidents
List of fatal accidents involving competitors
List of fatal accidents involving competitors
Rider Date_ Place Race Event Machine
George B Armstrong 1 September 1965 Sulby Bridge 1965 Manx Grand Prix Practice Triton
Toshio Fujii 26 August 1966 Cruickshanks Corner 1966 Isle of Man TT Practice 125cc Kawasaki
Brian Duffy 28 August 1966 Mountain Box 1966 Isle of Man TT Lightweight TT 250cc Yamaha
Alfred E Shaw 10 June 1967 Mountain Box 1967 Isle of Man TT Practice 500cc Norton
Geoffery Proctor 29 August 1967 Rhencullen Hill 1967 Manx Grand Prix Practice 248cc Cotton
Kenneth E. Herbert 1 September 1967 Doran`s Bend 1967 Manx Grand Prix Practice 499cc Norton
Ian D.Veitch 10 June 1968 Ballagarey Corner 1968 Isle of Man TT Lightweight TT Kawasaki

Question: Among fatal accidents on the Snaefell Mountain Course, which machine did Kenneth E. Herbert ride?