A Treatise on Foreign Teas is a book of Science. As two of the four meals that form our daily subsistence are chiefly composed of tea, an enquiry into what kind is the most salutary must be as necessary as it may prove interesting and beneficial; for, on the choice of proper or improper tea must greatly depend the health or disease of the public in general. To this may be attributed the constitution being either preserved from that innumerable train of afflictions, which arise from too great a relaxation of the nervous system by acute distempers, misfortunes, &c. or being so debilitated by excessive drinking of India Tea, as to render it alone the prey of melancholy, palsies, epilepsies, night-mares, swoonings, flatulencies, low spirits, hysteric and hypochondriacal affections. For tea that is pernicious is not only poison to those who, from any cause of corporal debility or mental affliction, are liable to the above diseases; but it is also too frequently found to render the most healthy victims of these alarming complaints. And as nervous disorders are the most complicated in their distressing circumstances, the greater care should be taken to avoid such aliments as produce them, as well as to choose those which are the most proper for their relief and prevention. Those who are now suffering from the inconsiderate use of improper tea, what pitiable objects of distress and disease do they not represent for the caution of those who may timely preserve themselves? Nervous disorders are the most formidable, by being the most numerous in their attacks upon the human frame. Every moment, comparatively speaking, produces some new distress of mind or body.