<P> The novel relates the plight of a widowed field mouse, Mrs. Frisby, who seeks the aid of a group of former laboratory rats and mice in rescuing her home from destruction by a farmer's plow, and of the history of the rats' escape from the laboratory and development of a literate and technological society . </P> <P> The work was inspired by the research of Dr. John B. Calhoun on mice and rat population dynamics at the National Institute of Mental Health from the 1940s to the 1960s . </P> <P> Mrs. Frisby is the head of a family of field mice . Mrs. Frisby's son, Timothy, is ill with pneumonia just as the farmer Mr. Fitzgibbon begins preparation for spring plowing in the garden where the Frisby family lives . Normally she would move her family, but Timothy would not survive the cold trip to their summer home . Mrs. Frisby obtains medicine from her friend Mr. Ages, an older white mouse . On the return journey, she saves the life of Jeremy, a young crow, from Dragon, the farmer's cat - the same cat who had killed her husband, Jonathan . Jeremy suggests she seek help in moving Timothy from an owl who dwells in the forest . Jeremy flies Mrs. Frisby to the owl's tree, but the owl says he cannot help until he finds out that she is the widow of Jonathan Frisby . He suggests that Mrs. Frisby seek help from the rats who live in a rosebush near her . </P> <P> Mrs. Frisby discovers the rats have a literate and mechanized society . They have technology such as elevators, have tapped the electricity grid to provide lighting and heating, and have acquired other human skills, such as storing food for the winter . Their leader, Nicodemus, tells Mrs. Frisby of the rats' capture by scientists working for a laboratory located at the National Institute of Mental Health (NIMH) and the subsequent experiments that the humans performed on the rats, which increased the rats' intelligence to the point of being able to read, write, and operate complicated machines, as well as enhancing their longevity and strength . This increased intelligence and strength allowed them to escape from the NIMH laboratories and migrate to their present location . Jonathan Frisby and Mr. Ages were the only two survivors of a group of eight mice who had been part of the experiments at NIMH, and made the rats' escape possible . Out of respect for Jonathan, the rats agree to move Mrs. Frisby's house to a location safe from the plow . </P>

Where does mrs frisby and the rats of nimh take place
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