The gearbox in "Babs"
A SMALL but interesting item occurs in that very readable book "I Kept No Diary" by Air Commodore F. R. Banks, which is reviewed elsewhere in this issue. It may be remembered that when writing some time ago of the Count Zborowski/Parry Thomas LSR car "Babs" I remarked that it has been stated, by other writers as well as myself, that when Thomas altered the former Liberty aero-engined Higham Special to his own requirements he retained the ancient gearbox from the 200 h.p. Benz that the Count had incorporated in his huge hybrid when this was constructed in 1923-4, but that Owen Wyn-Owen, the present keeper of "Babs", has told me that when he examined the long-wheelbase 200 h.p. Benz in the Birmingham Science Museum its gearbox casing was seen to differ from that in "Babs". This surprised me at the time, because it seemed unlikely that the long-wheelbase and racing Benz cars of this kind, both chain-driven, would not have had identical gearbox casings.
Now, having read Air Commodore Banks' book, I find that he refers to joining Peter Hooker Ltd. of Walthamstow, to develop the 1,500 h.p. Stromboli airship engine designed by Ettore Lanzerotti Spina and that some of the interesting jobs they had while he was there were building the 1 1/2-litre straight-eight engines for Patty Thomas' Thomas Special "flat-iron" racing cars and making the clutch and gearbox he had redesigned for "Babs". Hedley Thomson was General Manager of Peter Hooker Ltd., a company which had taken up licences to make Gnome and Le Rhone rotary aero-engines, and as he was the Thomson of Thomson & Taylor's of Brooklands, the link-up is understandable. Indeed, Thomas' four-cylinder engines for the first 1.5-litre and 1.8-litre Thomas Specials were made by Hooker's. I was not aware that the straight-eight engines were made there also, but Rod Banks remembers that they certainly machined the cylinder blocks, and he believes the crankshafts and con.-rods, for these engines, although they may have been assembled at Brooklands. Banks knew Parry Thomas quite well, he says, as he came frequently to Walthamstow and Banks also met him at Brooklands.
So far as "Babs" is concerned, it is known that Thomas abandoned the Mercedes scroll-clutch that Zborowski had used for the Higham Special, substituting a small multi-disc one of his own, and Air Commodore Banks says this was machined and assembled by Peter Hooker's. Banks has made no further mention of Hooker's making a redesigned gearbox for Thomas in correspondence I have had with him, and it all happened a long time ago, but in his book he does refer to this. Now when the Higham Special was proudly reversed out if its lair for the very first time in 1924 the late Col. Clive Gallop told me that the fierce clutch caused the reverse-shaft to break out of the gearbox casing. They tested the alloy of this casing, which dated back to perhaps 1907, and found that it had a very low tensile strength. (For metallurgists, Gallop told me this was only four tons.) Gallop was then sent post-haste by Zborowski to Mannheim, in Germany, where he secured the only remaining Benz gearbox of this kind. (The journey was made by air and I am still waiting patiently for a reader well versed in aviation matters to tell me which services and routes Gallop could have used for this journey in 1924, remembering the weight of the "parcel" he returned with.)
In view of this calamity with the original gearbox it does seem likely that even if Thomas retained the other Benz box's internals, or some of them, he might well have felt a new casing to be desirable before attempting speeds of over 170 m.p.h. with "Babs" and got Hooker's to make it.