1.) Suppliers: Look first in _Thomas' Register of
Manufacturers_. Next look in _The [Membership] Directory of The
American Institute for Conservation of Historic & Artistic
Works_, recent year - several advertise there. Also look in the
catalogs of Cole-Parmer Instrument Co., in the Chicago 'burbs -
1-800-323-4340 - and Fisher Scientific, 1-800-388-8355. Cost
$400 - $700 range, maybe a little less, maybe a little more.
2.) How many? How far is it into the woods? How high is up?
What this determination entails is nothing less than the design
of an environmental monitoring program. There are no cookbook
answers, and anyone who will tell you otherwise simply doesn't
understand the variables. Get a copy of William P. Lull and
Paul N. Banks, _Conservation Guidelines for Libraries and
Archives_, Ottawa: Canadian Council of Archives, 1995 (344
Wellington St., Rm 1009, Ottawa ON K1A ON3, abt US $40. Also
look at the two Commission on Preservation and Access
publications, _Isoperms_ by Don Sebera, 1994 and _New Tools for
Preservation_ by Reilly, Nishamura and Zinn, 1995.
Finally, I have seen postings for a series of workshops under
the auspices of the NEDCC, several given by Bill Lull, on
environment monitoring. (I went to the 1st, in Phila.) Contact
either NEDCC or Conservation Online Distlist at Stanford (which
is migrating to WWW). If I can help more, drop a byte.

According to ERIN E. GAMSE:
>
> Thank you for all the valuable information on hygrothermographs.  Now
> that I have digested it all, I have a new dilema.  If I were to look
> into purchasing a datalogger, where would I begin?  Who makes them?  Does anyo
ne
>  have the
> name of a supplier or two?  Who do you recommend?  How much are they?
>  How many would I need for a 2 floor  6,000 square foot exhibition
> space?  How many hygrothermographs would I need for that same space?
> Is there any literature on the subject of either hygrothermographs or
> dataloggers which I should read?
>