A concise view of the slavery of the people of colour in the United States : exhibiting some of the most affecting cases of cruel and barbarous treatment of the slaves by their most inhuman and brutal masters; not heretofore published: and also showing the absolute necessity for the most speedy abolition of slavery, with an endeavour to point out the best means of effecting it. To which is added, A short address to the free people of colour. With a selection of hymns, &c. &c. /