Lionel Chalmers of Charleston, South Carolina, came nearer to being a pediatric specialist than any other physician of the American colonial period. Although Douglass had written on scarlet fever, Bard on diphtheria, and Rush on infantile diarrhea, Chalmers not only published his observations on these diseases but also covered a much wider range of pediatric subjects. He appears to have been among the first in this country to appreciate that rickets did not include all bony deformities, that "nine-day fits" of infants was the same disease as tetanus of adults, and that thrush was not usually a primary cause of death. He also wrote on infant feeding, weaning, teething, worms, convulsions, impetigo and obstructive laryngitis. He was most original and perhaps at his best in his descriptions of whooping cough and mumps.