Speleology | Computing | Aviation | Gallery | Other | Mike Cowlishaw: contact details & biography
Welcome to the Speleotrove website: an accumulation of web pages, documents, and software.

 
Speleology Speleogroup; LED caving light designs, caving expedition logs, and other speleological projects (these are on the Speleogroup.org website).
See the 2013 expedition log for the latest trip report, and Mexico 1978/79 for our new transcription of an early trip to Mexican caves in Cuetzalan and Chiapas (and a climb up Popocatépetl).

Forcau ’76; the report of the Oxford expedition to the Pozo de Vega el Forcau. (OUCC proceedings 8, 1976, also available as HTML pages.)

The Characteristics and Use of Lead-Acid Cap Lamps, Cowlishaw, M. F., Trans. British Cave Research Association, Vol. 1. No. 4. pp199–214., December, 1974.   Summary: It was 1885 when the first portable rechargeable lamp was invented. The lead-acid cap lamp we know today has evolved in the ninety years since then, and has a high capacity together with many other advantages. This paper describes the construction and characteristics of these lamps, and discusses possible modifications, the use, and the maintenance of the most common types of lead-acid cap lamps.

OmniBUSS 5, The Journal of Birmingham University Speleological Society, Number 5, February 1974. Includes Expedition 1973, Picos de Europa, the first Speleogroup expedition.


Computing General Decimal Arithmetic: algorism for computers (and people) — an extensive collection of documents, links, and software for decimal arithmetic.

Tollos; a small supervisor program for microcontrollers using ARM Cortex M3 cores. It is intended to provide an efficient platform for low power applications, suitable for development boards and microcontrollers from multiple vendors. It is written entirely in C, and supports a number of peripherals, including graphics LCDs such as the DOGXL.

PMGlobe, a program which displays the Earth as a globe on Windows, showing night and day, local times, etc. It can be run as an application or as a screen saver.  (PMGlobe for OS/2 and Palm Globe for early Palm devices are also here.)

Fundamental requirements for picture presentation, Cowlishaw, M. F., Proc. Society for Information Display, Volume 26, No. 2 (1985).   Abstract: “How many bits per picture element does a display need?” For the display resolutions now commonly in use, only 4 bits per picture element (pel) are needed for the display of monochrome images. A total of 8 bits per pel are needed for color images. These conclusions are based both on experiment and on the theoretical model of the visual system in which the detectors in the eye are treated as simple photon-detectors. The results are applicable to “natural” images and also to computer generated images. A particular 8-bit color encoding scheme is described that also has the advantage that natural images are displayable on monochrome displays.

The Acorn 6502 Microcomputer Kit; a little piece of computer history—Acorn Computer’s first public offering, the Acorn Microcomputer (later known as the Acorn System 1). The one pictured on these pages was shipped on 9 April 1979. Also here is an Emulator for the computer, so you can try it for yourself even if you don't have the original hardware. It might also be useful as an educational resource, too, as it really shows how to program a computer at the hardware level (and with the mini-debugger you can watch the registers and other internal state changing as instructions are executed).

MemoWiki documentation snapshot. MemoWiki is a simple Wiki intended for personal documentation, research, and small-scale collaboration. It allows the viewing, editing, and maintenance of a collection of pages using just a web browser. To make it easy to support research, MemoWiki integrates its pages with academic references (which can be edited just as easily) and other files (such as papers, programs, and images).

NetRexx 2. Introduction, overview, and definition of the NetRexx programming language, version 2.
From the Introduction: NetRexx is a general-purpose programming language inspired by two very different programming languages, Rexx and Java™.  It is designed for people, not computers. In this respect it follows Rexx closely, with many of the concepts and most of the syntax taken directly from Rexx or its object-oriented version, Object Rexx. From Java it derives static typing, binary arithmetic, the object model, and exception handling. The resulting language not only provides the scripting capabilities and decimal arithmetic of Rexx, but also seamlessly extends to large application development with fast binary arithmetic.

NetRexx is now open source, maintained and enhanced by the Rexx Language association at the netrexx.org website. If you already know Java then Leonardo Boselli’s NetRexx at Once is a good starting point.

Also here are:

REXX is a programming language I created and implemented from 1979–1982. On this site is a REXX Language History collection, including a summary of its background philosophies, and also some REXX programs I have written.
The primary resources for REXX, along with historical links etc., are on the Rexx Language Association website. There is also a list of available REXX papers, etc., supervised by Prof. Rony G. Flatscher at WU Vienna (select ‘Rexx’ in the keyword list).

RexxCPS (Rexx Clauses Per Second); a list of RexxCPS results, showing the number of Rexx clauses per second observed on various combinations of hardware and operating systems since 1989.

LEXX is a text editor that I wrote while secondment to the Oxford University Press in 1985, for editing the Oxford English Dictionary. It was probably the first syntax-driven colour text editor. This LEXX-screenshots.zip file contains original 1986 front-of-screen shots of editing an OED entry (bungler), and also a number of later screen captures showing the use of LEXX for a variety of applications (including its own tutorial).

STET – A STructured Editing Tool; Description and Users Guide, Davies, S. and Cowlishaw, M. F., IBM UK Scientific Centre, Version 2: 28th Dec 1980. From the Introduction: STET is a first attempt to take the structure out of the domain of languages, and into the domain of editors. In addition to conventional editing facilities, STET gives the user a third dimension: a tree structure that may be traversed using Program Function Keys much as scrolling is normally implemented...
See also the Wikipedia article.

IEEE 754-2008 errata. The current version of the IEEE Standard for Floating-Point Arithmetic (IEEE 754) was published in August 2008 and was later approved as an international standard (ISO/IEC/IEEE 60559:2011). Since then, some minor problems have been noticed; this page lists those that I am aware of, with suggested corrections.

.EXE Magazine interview—Mike Cowlishaw, by Alun Williams, Feature Editor, .EXE Magazine, July 2000. (This interview was completed but neither edited nor published because .EXE magazine ceased publication with the August 2000 issue.)


Aviation Flying weather analyses: some experimental analyses of UK weather for 13 weather stations since 1997, with particular emphasis on wind strengths and Visual Flight Rules.

Experimental avionics: a description of some simple avionics applications I have written, implemented on a battery-powered device and using GPS and/or accelerometers.

The Flylight MotorFloater for FSX: my model of my MotorFloater Single-Seat Deregulated (SSDR) aircraft for Flight Simulator X. Here’s a screenshot: approaching Tresviso, over the Picos de Europa.

British Microlight Aircraft Association Flight Training Vouchers: as a Microlight Pilot, I’d like to encourage others to give it a try; through the BMAA you can buy a microlight flying lesson and start your training towards becoming a Microlight Pilot, or you can purchase a voucher for someone else as a gift.

The Sirocco Microlight: a collection of information on the Sirocco Microlight, a single-seat ultralight aircraft which has a pusher propeller, tricycle undercarriage, and 3-axis flight controls. Includes a description and history, several articles and other references, and some links to images and videos – including the new Sirocket.

The Spratt Controlwing Flying Boat—plans and construction notes. George G. Spratt's Controlwing flying boat was developed from 1939, with plans drawn up in 1972–1973. Bill Wolfe used these drawings to build N107GW in the late 1990s, and this page includes his annotated plans and an 84-page manual.

Long Marston R22 overhead join and circuits: an image showing flight tracks from a training session on 2008.10.29, departing to and returning from Shotteswell airstrip.

Pictures from Friedrichshafen 2010: 186 pictures that I took at the Aero show in April 2010. (These are reduced to 1024 pixels wide or high to save space, but the zip file still 31 MB.)

Pictures from Friedrichshafen 2011: 107 pictures that I took at the Aero show in April 2011. (These are reduced to 1024 pixels wide or high to save space, but the zip file still 19 MB.)

Pictures from Friedrichshafen 2012: 20 pictures that I took at the Aero show in April 2012. (These are reduced to 1024 pixels wide or high to save space; the zip file is 3.9 MB.)

Pictures from Oshkosh 2010: 179 pictures that I took at the EAA's AirVenture show in July 2010. (These are reduced to 1024 pixels wide or high to save space, but the zip file still 35 MB.)

Terry Viner’s airfields: a collection of UK airfields and airstrips in GPS Exchange Format (GPX).


Other Photo Gallery: a small selection of panoramas and stereo (3D) photographs of mine.

How to make SMT boards at home: pictorial showing the steps needed and a novel SMD component holder (also available at SpeleoGroup).

El Mazuco (the impossible defence); my translation of El Mazuco (La defensa imposible) by Juan Antonio de Blas, a chapter in La guerra civil en Asturias.

An Electricity Kit I built for my son in 1994.

Brandy Butter ‘ancestral’ Cowlishaw recipe (also for Rum Butter).

Wallace Breem (1926–1990) was a British librarian and author, and was the Librarian and Keeper of Manuscripts of the Inner Temple Library at his death in 1990. He was perhaps most widely known for his historical novels, including the classic Eagle in the Snow (1970).


This site was constructed and is maintained by Mike Cowlishaw. Please send me any corrections, suggestions for improvement, etc.

All text and images Copyright © Mike Cowlishaw 1973, 2012 except where stated otherwise. All rights reserved.
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