During the existence of slavery all credit for inventions was denied the Negro slave as a slave could not take out a patent. Nevertheless Negroes did most of the mechanical work in the South before the Civil War and more than one suggestion came from them for improving machinery. We are told that in Virginia: “The county records of the seventeenth century reveal the presence of many Negro mechanics in the colony during that period, this being especially the case with carpenters and coopers.”[61] As example of slave mechanics it is stated that among the slaves of the first Robert Beverly was a carpenter valued at £30, and that Ralph Wormeley, of Middlesex county, owned a cooper and a carpenter each valued at £35. Colonel William Byrd mentions the use of Negroes in iron mining in 1732. In New Jersey slaves were employed as miners, ironworkers, sawmill hands, house and ship carpenters, wheelwrights, coopers, tanners, shoemakers, millers and bakers, among other employments, before the Revolutionary War. As early as 1708 there were enough slave mechanics in Pennsylvania to make the freemen feel their competition severely. In Massachusetts and other states we hear of an occasional artisan.[62] During the early part of the nineteenth century the Negro artisans increased. The Spanish Governor Salcedo, early in the nineteenth century, in trying to keep the province of Louisiana loyal to Spain, made the militia officers swear allegiance and among them were two companies of colored men from New Orleans “who composed all the mechanics which the city possessed.”[63] Later, black refugees from San Domingo saved Louisiana from economic ruin. Formerly, Louisiana had had prosperous sugar-makers; but these industries had been dead for nearly twenty-five years when the attempt to market sugar was revived. Two Spaniards erected near New Orleans, a distillery and a battery of sugar kettles and began to manufacture rum and syrup. They had little success until Etienne de Boré, a colored San Dominican, appeared. “Face to face with ruin because of the failure of the indigo crop, he staked his all on the granulation of sugar. He enlisted the services of these successful San Dominicans and went to work. In all American history there can be fewer scenes more dramatic than the one described by careful historians of Louisiana, the day when the final test was made and the electrical word was passed around, ‘It granulates!’” De Boré sold $12,000 worth of sugar that year. Agriculture in the Delta began to flourish and seven years later New Orleans was selling 2,000,000 gallons of rum, 250,000 gallons of molasses and 5,000,000 pounds of sugar. It was the beginning of the commercial reign of one of the great commercial cities of America and it started with the black refugees from San Domingo.[64]