This is a re generated print (not a simple photocopy) of Chapter One of Air Publication (AP) 1743. Dated 1940.   This covers the Mk IX bubble sextant in detail from the operators standpoint. The original photographs were almost illegible so I have stripped my own instrument and taken new photographs as substitutes.  I have also assembled the pages into booklet form.  A5 16 pages in black and white with 6 illustrations.  The intent is to introduce the reader to the new sextant and gives a detailed explanation of it's principles of operation and construction with a thorough explanation of the averager. If you want to work on any of the MkIX sextants then this booklet will be essential starter as it covers the bubble chamber and optical path.
See https://g4osj.co.uk/Text/Catalogue.html  for more information



Postage (UK) £1.50



Please note that unless specifically stated otherwise in my listing all printed material is a facsimile. NOT original material.

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Feedback for this booklet:-
Happy.    Items received perfect condition. HIGHLY recommend this seller!!!!!!!!!!!!!!    Smooth and fast deal.    Ttres bon vendeur.  Very good.  Received safely, very well packed, very many thanks!!!  Item arrived quickly and as described. Good quality and clear.  Excellent seller, Fast delivery, Book 100%, Highly Recommended.  Fast and safe. Pefect item !!!! Perfect Ebayer !!!!!!!! Thank you.  Excellent and recommendable Seller; fast shipping; thank you; :-) :-) :-)  All good.  Excellent booklet. Outstanding service.