While the slave trade had been made illegal in 1820, it flourished with more or less vigor until the end of the Ten Years' War in the latter part of the century. Spain officially frowned upon it, but unofficially the Spanish crown is said to have been financially interested in the slave trading companies, and to have shared largely in their profits. To add to this incentive for the continuance of the trade, the Captain-General had his own reasons for not suppressing it. He was paid a fixed bonus for every slave imported. Indeed, the post of Captain-General of Cuba was one not to be despised by any soldier of fortune. The perquisites of the office are said to have been--of course, not from the slave trade alone--close to $500,000 a year. The Captain-General is said to have received "half an ounce of gold" for every "sack of charcoal," as they facetiously dubbed the negro, allowed to pass into the country. Although no excuse of expediency can be urged for the enslavement of human beings, no matter what their color or race, it remains a fact that the sugar plantations of Cuba required laborers in great numbers for their development, and the easiest and most profitable way to obtain that labor was through the employment of black slaves. It would probably have been impossible to obtain a sufficient number of white men at that time to do the work required, especially since when an attempt was made to import white men for work on the plantations, the owners who were of Spanish birth brought every influence possible to bear on the government to make such laws and regulations for that kind of labor that, if it could be procured, its retention was well nigh impossible. The blacks were naturally not satisfied with slavery. In their association with their masters they acquired just enough information and knowledge to make them dangerous. And at this time the blacks, free and slave, were a large majority of the population. The negro race in captivity was always difficult to manage. They were affectionate and responsive to good treatment but when their rage was aroused by hard and unjust treatment they reverted to habits of the jungle. The Spanish planters believed that the way to keep the negroes quiet was to keep them under with a strong hand and consequently overseers were frequently brutal. There began to be a strong undercurrent of unrest among the negro population, and an equally strong fear of them among the whites. Sporadic uprisings occurred, which were like the overflowing of a boiling caldron, not organized, and not well prepared, and therefore easily put down by the authorities. A description of a typical uprising of this character is contained in a work called "The Slaves in the Spanish Colonies" by the Countess Merlin, published about 1840. It relates the experiences of one Don Rafael with a mutiny of his slaves.