Tuesday, September 29, 2015

Manual of Barometry (WBAN) Now Online

This is the biggest news of our day, Sept 29, 2015.

While  working on updates to our Barometer Handbook, we found that the 1963 Manual of Barometry (WBAN) has now been scanned and available as a free download.  Apparently it was scanned the year following the publication of The Barometer Handbook.  I would like to think that our promotion of this rare, amazing book contributed to this?

WBAN is the Bible of mercury and aneroid barometers, as well as the basics of measuring barometric pressure... in fact, i wish there were a stronger way to put that description... maybe the Mother of all books on barometers... and altimetry.  It is the monumental work of Louis P. Harrison, but other than a note in the Preface he does not often get credit for it as he was an employee when he wrote it and this was an official "US Weather Bureau" document, numbered WBAN.

(The US Weather Bureau evolved out of the US Army Signal Corps in 1870s. It spent the 1880s in the Dept of Agriculture, and then became an agency of its own in the early 1890s. It moved into the Department of Commerce in 1965 where it resides today as the NWS in NOAA.)

We have had an extremely rare printed copy for many years, without which our work on barometers in general would have been much more difficult, and probably not as thorough.

It is not easy reading; most of the thousand or more pages are pretty technical... in some cases really specific (ie taking into account your latitude and the shape of the earth when computing the weight of mercury and your height above mean sea level), but if you have a question about how to use barometers for getting accurate pressure, then this is the primary source, and we list is as such in our own books.

It also includes one of the first compilations of the fudge factors used to convert observed pressures at higher elevations to realistic sea level pressures, the need of which was first recognized by the American scientist William Ferrel in the1880s. He called this the plateau effect and these constants are still in use today.*  Ferrel also discovered the Buys Ballot law (which was even acknowledged by Buys Ballot himself) and he was first to apply the concept of Coriolis force to the circulation of global air masses, and as it is generally used today,  can be thought of as having invented that as well... though this has a bit more nuanced history.

Find the pdf here:

Manual of Barometery WBAN

What you do with accurate pressure once you get it is discussed in our books Modern Marine Weather and The Barometer Handbook.

Note that the title page calls the book Volume 1, and the Preface refers to what was intended for Volume 2, but to our knowledge, there is no Volume 2 — when you finish this one, I am sure you will be dying for more, but I am afraid this is all there is.

We also have a list of articles on barometers.


* Ferrel in the 1880s also showed that the outside air temperature needed to make the conversion between station pressure (ie at elevation) to sea level pressure should not be the present air temperature, but rather the average of the present temperature and that of 12 hours earlier.  We did a study in 2013 that confirms this is indeed the case. See Air Temperature Dependence of Sea Level Pressure Conversions

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