Missouri Compromise
2 of the 7 encyclopedias on this shelf carry an entry for Missouri Compromise. Both are reproduced below, so you can see where they agree and where they differ.
Aiton's Encyclopedia (1910)
in American history, a measure dividing the Louisiana Purchase into free and slave territory. In order to avoid disturbing the balance in the Senate new states were admitted in pairs. Thus, subsequent to the admission of Louisiana, Indiana and Mississippi, and Illinois and Alabama were paired. When Maine and Missouri came forward the North insisted that the latter belonged to the West rather than to the South, and that it should be admitted as a free state. The settlers of Missouri were largely slave-holders. In 1819 an act, known as the Missouri Compromise Bill, was passed admitting Maine as a free state, but authorizing slavery in Missouri. A clause was added by way of compromise forbidding slavery in the Louisiana Purchase north of 36 deg 30' north latitude except in Missouri. The North was reasonably well satisfied with having fixed a limit north of which the institution of slavery should not gain a future footing. The South was exasperated. John Randolph of Virginia called the compromise feature, "a dirty bargain." In fact the South never accepted the compromise in good faith. When Kansas came up for admission, southern congressmen and senators, together with Stephen A. Douglas and others, openly advocated the repeal of the act and set up the principle of squatter sovereignty or local option. See Kansas ; John Brown
Collier's New Encyclopedia (1921)
a term given to a compromise under an act of Congress passed in February, 1821, at which time Missouri was admitted into the Union as a slave State, declaring that all territory W. of Missouri and N. of lat. 36° 30' (the S. boundary of Mis- Belmore Browne EXPLORERS ON THE SOUTHERN SIDE OF MT. MCKINLEY, ALASKA. THIS IS THE HIGHEST PEAK IN NORTH AMERICA Enc. Vol. 6-p. 260 DE Ewing Galloway INTERIOR OF A PLANT FOR REGRINDING COPPER, IN THE COPPER DISTRICT OF MICHIGAN A VIEW OF MEMPHIS, TENNESSEE, ON THE MISSISSIPPI RIVER Ewing Galloway A MISSISSIPPI RIVER STEAMER AND A DOCK FOR RICE, NEW ORLEANS Ewing Galloway HIDES FROM ARGENTINA, UNLOADED FROM A JAPANESE STEAMER AT NEW ORLEANS Photo, British and Colonial Press