Arthur Hezlet

Published in 1975, this is a history of the use of electronics and electricity in naval activities from initial use till the 1970s. It covers such subjects as undersea cables, wireless communications, radio frequencies and the development of radar in detail, but also concerns itself with more diverse topics such as the installation of electric lighting in warships, as well as other electrically powered devices. It also delves into the use of electricity to power warships, and even the development of searchlights. The book really shines in the details of wireless communications from the beginning through WW1, something I knew little about and the book covers in quite a lot of detail. Very highly recommended.… (més)

Obsolete as far as current naval equipment is concerned – the cover illustration includes a vacuum tube – but interesting for history. I was intrigued to find that the initial application of electricity to naval power was the use of the telegraph – now orders and information could be sent to naval vessels on distant foreign stations (sometimes to the annoyance of naval officers who were used to being on their own). (see rel="nofollow" target="_top">Nexus for a discussion of the use of cables during WWI).

Cables were supplemented and partially replaced by radio. The early radios were various kinds of intermittent spark and arc transmitters – they could only send dot-and-dash code, not voice, and that only slowly, such that they could only be used to send general orders, not detailed maneuvering instructions. Originally there was no way to tune them – they broadcast on all wavelengths at once, so if more than one ship tried to transmit at the same time the signal was hopelessly garbled. The early radios were line of sight – ships couldn’t transmit over the horizon. And officers were reluctant to use them because they were afraid radio signals would give their position away to the enemy. Most of these things were gradually worked out; radios were developed that could be tuned and allow voice transmission, and it was discovered that ground waves and bouncing radio off the ionosphere allowed transmissions over global distances. Radio direction finding was (and remains) very important; enemy ships could be located by triangulation, and this figured heavily in WWI and WWII naval battles. Not only could radio direction finders locate enemy ships, but the enemy’s signals could be intercepted and decoded. Author Sir Arthur Hezlet notes this was very important in WWI, when both the British and the Germans had considerable success reading each other’s codes, but expresses regret that it wasn’t as successful in WWII – obviously he wrote this book before Ultra was declassified.

Another application that didn’t occur to me was searchlights; we’re so used to radar in naval warfare that searchlights seem to be limited to big movie openings, but they were once extremely important for night actions and every warship had some, often several. There was a synergy between the development of the torpedo and the development of the searchlight; the torpedo gave small boats a weapon that could sink the largest battleship – but only if it could be launched before the torpedo boat was blown out of the water by gunfire from the target vessel. The solution to that was to make the torpedo attack at night; and the response to that was the searchlight. There was an arms race – as the size and range of torpedoes increased, the size and range of searchlights increased in response, until ships were equipped with multiple 36” to 48” searchlights. Radar eventually took over the job, of course.

Another nonobvious application of electronics was gunnery control. In the early days of naval guns, you didn’t shoot until you were alongside the enemy and actually aiming the gun slowed things down; the muzzle-loading cannon of the age of sail usually didn’t even have gunsights. As cannons continued to develop, however, the range increased to the point where aiming them was necessary. At first this was left to the individual gun captains and gunners. As ranges increased that became problematical too; you fired your gun and sometime latter there was a splash near or a hit on the enemy vessel; but every other gun on your ship was also banging away – so since one splash looked more or less like the others how did you tell which gun had the range and was aimed accurately? The solution here was central control with salvo firing; an officer – up on a mast somewhere with an intercom and a firing control – gave the bearing and elevation to all the gun crews and fired all the guns at once, electronically. Then that officer would note if the splashes were ahead, behind, over or short of the target, adjust the range and bearing, and do it again until hits were scored.

Paradoxically the sections of the book covering more recent events were less interesting – to me at least. There’s extensive discussion of radar and sonar use in WWII, but I was already fairly familiar with that from other reading.

Illustrations include maps of cable and radio coverage in the early days, line drawings of searchlight locations on ships, and photographs of ships with the locations of various radar sets. A short bibliography. There’s an extensive endnotes sections; some of these might have been better if included in the main text. Recommended for naval historians, especially if interested in the preWWI and WWI eras.… (més)