Dr. Clark retired from rocket research in 1970 and his long-suffering wife was an impetus for him publishing an account of his experience and expertise in 1972. The stated purpose of Ignition - An Informal History of Liquid Rocket Propellants [archive.org] was for people to avoid repeating mistakes. Indeed, if the contents were more widely understood, particularly the three references to O-rings and numerous references to temperature, the Challenger [wikipedia.org] disaster [wikipedia.org] could have been avoided. The chapter on energy density should also be read more widely because, in 1970, LiH was used to start rockets rather than make batteries which, predictably, catch fire. Likewise, if the USAF had heeded Dr. Clark's advice against the disclosure of a particular technique, SS-1 "Scud" missiles [wikipedia.org] may have been less effective against US personnel.
The book provides a brief and functional history of rocket chemistry before it expands massively into Dr. Clark's first-hand knowledge. No attempt is made to explain rocket hardware which can be obtained from numerous other sources [aardvark.co.nz]. Dr. Clark's personal technical contributions conclude the longest chapter and this concludes within the first half of the book. The remainder of the book is a number of advanced topics which progress after the industry checkpointed with the success combination of RFNA [wikipedia.org] and UDMH [wikipedia.org].
Dr. Clark's remaining experience is mostly in an adminstrative capacity of running a chemistry laboratory or the practicalities of industrial test standardization. His speciality was the two types of explosive test. He generally avoided compounds which exceeded a cellulose card-gap test from 30 to 35. Compounds which exceeded this or other limits often led to hurried telephone calls to other labs. Unfortunately, this was too late for one chemist who was blinded in one eye and lost four fingers in an avoidable incident. Numerous people were killed or hospitalized. Although researchers rapidly shied away from the most dangerous compounds, this often came too late for one or two people:
RFNA attacks skin and flesh with the avidity of a school of piranhas. (One drop of it on my arm gave me a scar which I still bear more than fifteen years later.) And when it is poured, it gives off dense clouds of NO2, which is a remarkably toxic gas. A man gets a good breath of it, and coughs a few minutes, and then insists that he's all right. And the next day, walking about, he's just as likely as not to drop dead.
Despite such hazards, Dr. Clark was proud of 17 years running a lab with no lost days due to industrial accidents. However, he worked in an environment which was awash with government funding - with up to nine labs known to be working on a trendy topic - and therefore he had the luxury of outsourcing manufacture of toxic salts and mercury compounds. Regardless, for anyone who enjoys Things I Won't Work With [sciencemag.org], this is similar craziness in a longer form. I laughed outrageously over numerous incidences.
Some work was deployed in Nike Ajax [wikipedia.org], Atlas [wikipedia.org], Titan [wikipedia.org] and Saturn [wikipedia.org] rockets but work was often superceded before a test rocket was fired. Unfortunately, rocket tests reveal very little. A successful test obtains data about exhaust temperature, smoothness of ignition and any unexpected byproducts. Whereas, the most useful data-point from failure was the extent of destruction. Did the engine melt? Was a camera lens merely cracked or smashed to dust? Was a re-inforced test chamber blown out? Metric [wikipedia.org] and US units [wikipedia.org] are used interchangably but a test engine with a 50 pound thrust was deemed unsatisfactory because it was easily gummed and this adversely affected the accuracy of extrapolation. Ignition - An Informal History Of Liquid Rocket Propellants often reads like Mad Men [wikipedia.org] or a scientific B-movie [wikipedia.org]. One test failure involved a test engine shooting 600 foot (200m) in one direction and its baseplate shooting 1400 foot in the opposite direction. While a technician shouted "My God, Doc! What the Hell did you send us this time?", Dr. Clark calmly lit a cigarette and made reference to a cocktail. The book is also gloriously politically uncorrect with Italian, Greek, Jewish and Russian stereotypes. It is also sexist. Secret compounds were named after favorite secretaries. It is completely unaware of environmental concerns beyond unexpected interaction with wildlife. For example, during the development of particularly smelly sulfur compounds:
The odor of these was not so much skunk-like as garlicky, the epitome and concentrate of all the back doors of all the bad Greek restaurants in all the world. And finally he surpassed himself with something that had a dimethylamino group attached to a mercaptan sulfur, and whose odor can't, with all the resources of the English language, even be described. It also drew flies.
CFC-13 [wikipedia.org] gets a passing mention but only in the context of an additive to homogenize ozone fuel. Readers of the book will gain a detailed appreciation of starting, adjusting, stopping and re-starting a rocket. Readers will also gain appreciation of design considerations for JATO [wikipedia.org], arctic warfare, cruise missiles [wikipedia.org], SAMs [wikipedia.org], ICBMs [wikipedia.org] and rockets to various parts of the solar system. Readers will learn why anything outside of CHON [Carbon, Hydrogen, Oxygen, Nitrogen] [wikipedia.org] should be viewed with suspicion and why it is important to recover catalysts in full. Readers will obtain a comparison of liquid, solid, hybrid, reverse hydrid rockets covering WFNA [wikipedia.org], RFNA [wikipedia.org], IRFNA [everything2.com], MMH [wikipedia.org], UDMH [wikipedia.org], LOX [wikipedia.org], FLOX [braeunig.us], petroleum [wikipedia.org], diesel [wikipedia.org], kerosene [wikipedia.org], ozone [wikipedia.org], ammonia nitrate [wikipedia.org], azines [wikipedia.org] and other compounds. Readers will also gain cursory appreciation for nuclear rockets [wikipedia.org] and ion thrusters [wikipedia.org]. The book contain extensive details about starter slugs, hypergolic [wikipedia.org] fluids and fuel additives to reduce viscosity, freezing point, unwanted catalytic conversion, container corrosion, toxic fumes, shock sensitivity and other properties. Viscosity and freezing point is a particular problem when, for example, desirable trinitro molecules form crystal structures due to van der Waals [wikipedia.org] forces [wikipedia.org].
Gain insight into the historical process of military standards such as JP-1 [wikipedia.org], JP-4 [wikipedia.org] and RP-1 [wikipedia.org]. Unlike other chemistry books, readers will also get a feel for the timescale of development; which tasks take a morning, a day, a week, a month or longer. Less than one page on computing explains why scientific users clambered to use ARPANet [wikipedia.org]. GIGO [wikipedia.org] and computer rage [wikipedia.org] were already understood before 1970. However, one punch-card [wikipedia.org] deck for an IBM 360 [wikipedia.org] saved a month or more of slide-rule [wikipedia.org] calculations and was often more precise even if the compounds were fictitious. A summary of Russian and Chinese technology is equally terse yet insightful. Overall, it provides a nuanced snapshot of government and industrial chemical research centered around the Anglosphere from 1950 to 1970.
The mathematics rarely goes beyond logarithms [wikipedia.org], asymptotes [wikipedia.org] or simultaneous equations [wikipedia.org]. However, advanced topics require an understanding of chemical phase diagrams [wikipedia.org], bromide [wikipedia.org] catalysis [wikipedia.org], SF6 [wikipedia.org] solvent [wikipedia.org] and petroleum chemistry which may have fallen out of general circulation. Being a typical chemistry book, there is an extensive glossary and index. This is thankful because acronyms are used with little introduction.
As a test of knowledge gained, I wondered what would be a suitable fuel to power an amateur rocket nowadays. 20 years ago, something akin to JP-4 would be a safe choice but when, for example, the French Government wishes to ban petrol and diesel by 2040 [soylentnews.org], available hydrocarbons may not be widely available even if they remain affordable. I couldn't remember the details but I wondered if acetone [wikipedia.org], urea [wikipedia.org] or, from the text, methyl methacrylate [wikipedia.org] would be suitable. Indeed they are. CO(CH3)2 [acetone] and CO(NH2)2 [urea] are particularly suitable CHON molecules which are exothermic [wikipedia.org], react at sensible temperatures and have light, high-velocity byproducts which move out of the way promptly. Unfortunately, reports from the fashion industry indicate that nail varnish is being developed which does not require the use of "toxic" acetone. Next, they'll be extracting the urine [urbandictionary.com].
Ignition [benkahtan.com] is of general interest to armchair pyromaniacs. It is also of interest to boat, car and plane enthusiasts. (Full scale and model scale.) It provides background for many industrial chemical processes including battery technology and two-part plant nutrient. A PDF with SHA512 0d7de74ba4ffbac2aa425c0b203bc14d3aee81b55b8039320156918f736e4d039ef3f0889da9530635f161c2e9dae974eb7c4d92a2150e66e73bd534534cbca4 is widely available [archive.org].