This museum is found in the Chicago museum campus. It was started way back in history as Columbia Museum of Chicago. Its core reason why it was established in 1893 was to collect and preserve educative objects in various subjects. It is one of resourceful museums in terms of history, science and archeology. It is named after Marshall Field who was the benefactor and that is how it changed its current name. After changing its name in 1905 it started concentrating on the natural science. Originally it housed some of the Columbia Exposition of 1893.
If you book in any of the Chicago hotel rooms you can be sure of getting more information on this museum. The museum nowadays is a permanent exhibit of several nature topics. These topics include Eskimos, bird habitats, sea mammals, animal biology, fossils, Native American cultures, gems, and many more. In the museum website you will find some of the current additional collections from all over the world. You will never get bored in this museum due to it interesting natural history that is always changing.
Recommendable sites on information about the museum
http://www.chicagotraveler.com/attractions/the-field-museum.html
http://www.flickr.com/groups/fieldmuseum/
http://gochicago.about.com/od/chicagomuseums/p/field_museum.htm