How did personal liberty laws increase tensions between the north and the south over the fugitive slave act?

Some northern states used personal liberty laws to nullify the Fugitive Slave Act, written to help the South.

probally   a few days after there called

aug 15, 2012 - although van leeuwenhoek was not the inventor of the microscope, he advanced it more he loved to grind and focus a new lens in order to see the unseen world. most of leeuwenhoek's microscopes were silver. in a simple but significant experiment (1668), he demonstrated that worms found on