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Hush-Hush - The Story of LNER 10000

Hush-Hush - The Story of LNER 10000 by William Brown
published in 2010 by Kestrel Railway Books
ISBN 978-1-905505-15-9
a review by Chris Newman
(taken from his Amazon book review)

Hush-Hush book cover

This book is a "prequel" to "Fowler's Fury: The Story of a Unique British Steam Locomotive" by Ian Carney (published in 2012) and describes a parallel and equally fascinating experiment in high pressure compound expansion in the form of Gresley's 4-6-4 No 10000, famously known since its inception as the "Hush Hush".

The book documents Brown's researches of the NRM's archives through which he has unearthed much new information about this once secretive project, sufficient to create a fascinating and revealing story. Sadly, however, the author fails to capitalize on it and leaves far too many gaps unfilled. His publisher should perhaps have advised him to recruit a co-author with the competence to contribute a greater level of technical authority, or to have submitted the manuscript for critical review by such a person.

Critical questions arise from page 1, on which the author alludes to "one massive and highly significant schoolboy error" which compromised the success of the locomotive during its first two years of operation. Thereafter he leaves the reader in suspense until he gets to page 70 when he attempts (and fails) to explain what the error was. [It was somehow related to the "woeful arrangements for auxiliary steam", but that is all we seem to be told.]

The author's attempts to explain the principles of thermodynamics also pose more questions than they answer, as does his explanations relating to the terms "work" and "efficiency". The same happens when he attempts to explain the principles of compounding, saying that "... it is the volume of steam that is doing the work and the two cylinders must be seen as one, in two steps. This means that the high pressure, first stage will be at full boiler pressure for most of its stroke, no matter how short the cut-off in the equivalent simple expansion cylinder". No doubt he understands the meaning that he is trying to convey, but this reader struggled with it. Similarly his deductions about the advantages of compounding are equally puzzling, for instance where he describes a two-cylinder compound as "potentially efficient enough to be equivalent to a two cylinder simple, intuition suggesting using half the quantity of steam". One must be thankful that L.D. Porta was better able to explain such concepts in his "Compounding" paper as published in Advanced Steam Locomotive Development (Camden Miniature Steam).

Even more troublesome is a lengthy quotation from a contemporary (1930) American report that discussed the performance of the Baldwin experimental compound locomotive No 60000, which includes an intuitively contrary statement: "If steam of 200 psi and of 350 psi is expanded from the same temperature under such conditions in each case respectively that the exhaust steam escapes at the same temperature and pressure, and with the same heat content in both cases, it follows that the heat taken from the steam in the cylinders and converted into mechanical work will be slightly less with high than with low pressure steam. That is, with the same heat content in the exhaust steam, the higher pressure will not give greater thermal efficiency." No doubt the author quotes the words as they were written, but he offers no refutation of what is intuitively and factually an incorrect statement. [The solution to this apparent conundrum can be found on the Thermodynamic Anomalies page of this website.

At a simpler level, the author's reference to William Webb's "highly successful compounds, especially on the LNWR" might  also puzzle the reader, but perhaps Webb's successes have been overshadowed too much by his failures.

Listing all the questions that Brown's book raises in this reviewer's mind could fill another book. Hence it must suffice to mention just one more of its deficiencies, namely the lack of a diagram to explain the unusual and complex arrangements for the flow of combustion air from the front of the locomotive through to the rear of its ashpan, and the flow of combustion gases from the firebox through and around the water tubes to the smokebox. The author expends many words describing these flows (with frequent reference to baffles), but none offer a clear explanation. The cut-away diagram that he provides also fails to present a clear picture of how these gases were channelled - the reader being left, if he can, to discover the answer via the Internet.

As with "Fowler's Fury", the lack of an index in Brown's book adds further to the reader's frustrations.

Yet, disappointing though it may be, the book contains large amounts of valuable and previously unavailable information about what was a historically important and worthy (if misdirected) experiment aimed at improving steam locomotive technology. I therefore have no regrets about buying it.

This book may be purchased from Camden Miniature Steam Services and other retailers.