<div class="description">
<p>Bausch &amp; Lomb Spectronic 20 Colorimeter (title page verso) from <i>Bausch &amp; Lomb Spectronic 20 Colorimeter Cat No. 33-29-40, Reference manual</i>.  Rochester, New York: Bausch &amp; Lomb Incorporated, [1962].
</p><p>Note: The date of 1962 is based on the last two digits of the code on the back cover, "332940-181ND, 600, II-62".
There is no copyright statement in the manual, and no copyright registration renewal for the manual.  It is therefore in the public domain in the United States of America. 
</p>
The photograph features a young woman sitting at a colorimeter and writing down results. The caption on the original page reads: "B&amp;L Spectronic 20 Colorimeter".</div>
<div class="fn value">
Unknown<span style="display: none;">Unknown </span></div>
1962<div style="display: none;">date QS:P571,+1962-00-00T00:00:00Z/9</div>
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