The Youden pH Meter : Notes from the Oesper Collections, No. 33, July/August 2015

Our recently acquired Youden null-point pH meter. The Moir electrode system, minus one of the salt bridges, is to the left and a circa 1940 bottle of quinhydrone is displayed between it and the meter.
Our recently acquired Youden null-point pH meter. The Moir electrode system, minus one of the salt bridges, is to the left and a circa 1940 bottle of quinhydrone is displayed between it and the meter.

Issue 33 describes a recently acquired compact pH meter from the 1940s that uses a quinhydrone electrode, rather than either a hydrogen electrode or a standard glass electrode.

Click here for all other issues of Notes from The Oesper Collections and to explore the Jensen-Thomas Apparatus Collection.

Countercurrent Distribution Once Again : Notes from the Oesper Collections, No. 32, May/June 2015

The circa 1949 Craig cylindrical countercurrent distribution apparatus recently donated to the Oesper Collections by Dr. Edward Bennett (Jensen-Thomas Apparatus Collection).
The circa 1949 Craig cylindrical countercurrent
distribution apparatus recently donated to the Oesper Collections by Dr. Edward Bennett (Jensen-Thomas Apparatus Collection).

Issue 32 describes the recent acquisition of an even earlier version of a Craig countercurrent distribution apparatus than the version that was described in issue 3 of 2010.

Click here for all other issues of Notes from The Oesper Collections and to explore the Jensen-Thomas Apparatus Collection.

The Siemens Elmiskop 1A Electron Microscope : Notes from the Oesper Collections, No. 30, January/February 2015

Front view of the Siemens IA Elmiskop in its original location at UC Environmental Health and Safety.
Front view of the Siemens IA Elmiskop in its
original location at UC Environmental Health and Safety.

Issue 30 of Museum Notes highlights the recently acquired, circa 1964, Siemens Elmiskop 1A Microscope now on display on the upper mezzanine of the Chemistry-Biology Library in 503 Rieveschl.

Click here for all other issues of Notes from The Oesper Collections and to explore the Jensen-Thomas Apparatus Collection.

Oesper News: Museum Booklets on the History of Chemical Apparatus

Dr. William B. Jensen introduces his new series:

Like most museums, only about 25% of the holdings of the Oesper Collections
in the History of Chemistry are on public display at a given time. In order to make the remaining 75% available in some form, it was decided to initiate a series of short museum booklets, each dedicated to a particular instrument or laboratory technique of historical importance to the science of chemistry.

Each booklet would include not only photographs of both displayed and stored museum artifacts related to the subject at hand, but also a short discussion of the history of the instrument or technique and of its impact on the development of chemistry as a whole. Several of these booklets are expansions of short articles which have previously appeared in either the bimonthly series Museum Notes, which is posted on the Oesper website, or the series Ask the Historian, which appeared in the Journal of Chemical Education between 2003 and 2012.

You can access the booklets by clicking here.

 

Who Invented the Fleaker? : Notes from the Oesper Collections, No. 29, November/December 2014

Typical modern-day fleakers with their patented caps.
Typical modern-day fleakers with their patented caps.

The 29th issue of Museum Notes highlights a recent innovation in laboratory glassware known as the “fleaker” and traces its historical antecedents to a late 19th-century innovation known as the “beaker flask.”

Click here for all other issues of Notes from The Oesper Collections and to explore the Jensen-Thomas Apparatus Collection.

The Twitchell Hydrometer : Notes from the Oesper Collections, No. 28, September/October 2014

A brass hydrometer jar with handle and thermometer and two metal hydrometers probably designed to monitor the fermentation of beer
A brass hydrometer jar with handle and thermometer and two metal hydrometers probably designed to monitor the fermentation of beer.

The 28th issue of Museum Notes highlights yet another scientific instrument produced by the 19th-century Cincinnati inventor Henry Twitchell (1816-1875).

Click here for all other issues of Notes from The Oesper Collections and to explore the Jensen-Thomas Apparatus Collection.