Charles Cave (Figure 1) is arguably the most under-appreciated British meteorologist of the First World War. The fault undoubtedly lies with his obituarists who, despite being his contemporaries, totally ignored his wartime service in the meteorological office at the South Farnborough Royal Aircraft Factory (R.A.F.), where he worked from February 1915 until the end of May 1917 – and was actually the Officer-in-Charge for all but the first eight months (Gold, 1951; Peters, 1951; Watson-Watt, 1951). Only Hawke (1951), who briefly worked with Cave, makes any mention of his time there.
Watson-Watt also effectively reduced Cave to a minor role in his autobiography, which is strange as he was Cave's deputy at the aerodrome from the autumn of 1915 until the summer of 1917 (Watson-Watt, 1958). The reason Watson-Watt adopted this approach is unclear, unless it was a desire to claim all the credit for developing a system for locating and tracking thunderstorms from bearings taken on atmospherics (sferics) created by lightning discharges.1 The fact of the matter is that, when Watson-Watt first arrived at South Farnborough, Cave had not only developed a crude -system with the assistance of a radiotelegraphic expert of the R.A.F., Dr R. Whiddington (later Major Whiddington of the Royal Flying Corps), but shortly after Watson-Watt's arrival wrote the very first paper describing the concept (Cave, 1915) – a paper which the Director of the Mete-orological Office, Dr W. N. Shaw, inexplicably failed to publish (Booth, 2009).
Shaw redeemed himself to some extent by ensuring, as the meteorological representative on the Advisory Committee for Aeronautics, that Cave's work in this area of meteorological research was recognised in the Committee's Annual Report for 1917–1918 (Rayleigh, 1918):
The work was carried on by Captain Cave, R.E., with the assistance of Mr R. A. W. Watt, until June 30th, when Captain Cave was transferred to the Office at Kensington in order that he might bring the experimental work into daily practical relation with the forecast service.2 Part of the work transferred with him, and he retained Superintendence of the enquiry.
Unfortunately this is not widely advertised so, given the lack of recognition of his First World War work by those who knew him, it was not surprising that later writers, for example Ratcliffe (1993), also failed to appreciate Cave's invaluable contribution to the war effort and meteorology.
Atmospherics apart, Cave contributed greatly to the work of the R.A.F. and in an era of mechanical uncertainty his ideas were innovative and directed towards finding means that made flying safer – for example, locating the positions of thunderstorms with a view to issuing warnings. The network of stations he developed to track atmospherics was not only the first such network nationally, but also globally. In a more practical sense, in respect of observing, Cave was the first British meteorologist to use a searchlight to measure cloud bases at night (Booth, 2009).
Cave was passionate about all aspects of practical meteorology and it was a passion he combined with his other great love, photography – with clouds being a favourite subject (Cave, 1926). During his life he created an impressive archive of glass plates of cloud images which, after his death, was acquired by the Royal Meteorological Society. Now held by the National Meteorological Archive, on behalf of the Society, the archive is incomplete due to losses and breakages, while the images on some of the early plates are breaking up. However, amongst those that survive are three aerial images of clouds: there is no indication as to their locations – two, dated 29 January 1916, are simply listed as being Taken at 11.00 am showing stratocumulus from aeroplane just above clouds. The third is an earlier photograph for which the only information given on its folder is ‘Taken on ?? September 1915 at noon, showing stratocumulus at 4000 feet from above’. In the event, research has shown that this photograph and the flight on which it was taken has a small, but notable, place in British meteorological history.
Although Cave left no personal account of his life during the First World War, a record of flights made at South Farnborough survives. Among the entries in the document3 is one for 15 September 1915 which records that Captain Cave (he had been commissioned into the Royal Engineers the previous June) was taken on a 30-minute flight by William Stutt (Figure 2) for cloud photography, the aeroplane taking off at 11.45 am. These details exactly fit those given on the otherwise undated plate in the Cave collection.
The words ‘for cloud photography’ are significant, for they mean that the flight is the first confirmed instance of an aeroplane being used specifically for meteorological purposes in the United Kingdom. As the R.A.F. had no history of interest in meteorological research, the flight could only have been made at Cave's behest: he referred to Stutt as being a somewhat experienced observer of clouds (Cave, 1917). The photograph's significance is not its composition, indeed it is unexceptional (Figure 3), but that it was the end result of this first flight. The aeroplane was an RE 7, serial number 2348 (Figure 4), in which Cave would have been seated in the front cockpit, not the best position for photography as his -forward view was restricted by the engine and his side view by wing struts and bracing wires.
The R.A.F. flight log book is not definitive in that not all flights are recorded: there is no record of Cave making a flight on 29 January 1916. Fortunately the two photographs taken on this date were included in Cave's The Form of Clouds (1917), which not only identifies them as being taken at South Farnborough but also that the cloud top was at 3000 feet. Only one of the photographs is reproduced here (Figure 5), the plate of the second having deteriorated over the years. Despite the lack of written evidence there is sufficient of the aeroplane visible to identify it as being a FE2b (Figure 6), in which he would have been sitting in front of the pilot giving him an excellent all-round view.
After 1916 there are just two more recorded instances of Cave making flights for cloud photography, both in May 1917, shortly before he moved to a new post at the Headquarters of the Meteorological Office at Kingsway in London. The second of these, on 23 May, carries the intriguing caveat that the aeroplane, an RE 8, which took off at 2.15 pm (British Summer Time) ‘came down at Petersfield’. This was something of an understatement. Cave's pilot on this flight was the R.A.F's. chief test pilot Captain Roderic Hill (later Air Chief Marshal, Sir Roderic Hill). Hill's future wife taught at Bedales School, about five miles due north from Ditcham Park where Cave lived, and he was wont to impress her with his flying ability by performing aerobatics at low level; unfortunately on this occasion things did not work out quite as planned, and the aeroplane was destroyed when it crashed a short distance from the school – Hill's only injury being hurt pride (Hill, 1962). Neither Hill's account, nor that of the headmaster of Bedales School (Anonymous, 1917), makes any reference to a passenger. However, Cave was an enthusiastic supporter of aviation, and aeroplanes visited Ditcham Park on occasion, landing on the extensive lawns. Consequently his absence from the scene of the accident is almost certainly explained by his having -disembarked at his home a short while previously.