A treatise on the synochus atrabiliosa, a contagious fever : wich raged at Senegal in the year 1778, and proved fatal to the greatest part of the europeans, and to a number of the natives : to which is prefixed, a Journal of the Weather during the Prevalence of that disease ...: and annexed to it, a short reflexion on the gum trade of Senegal, and the importance of the place on that account