The plan annexed to this pamphlet will exhibit the two lines, and the reader will perceive that a small Lake, called the Lake of Vino Tinto, may, if the first proposal is adopted, be made available, and so lessen the extent of the Canal. If the Rivers are used as a part of the Navigation, the distance between that point of the River Trinidad at which the Canal would commence, as shewn in the plan, and the point where the Farfan ceases to be navigable, is only 25 miles, and there is no high land intervening, the chain of the Andes terminating several miles to the eastward of the valley of the Chagres, as before mentioned. If the other plan be adopted, the length of the Canal will be 58 miles. Although at first sight it may appear to be a work of supererogation, to carry the Canal over that part of the Isthmus which is traversed by navigable rivers, it is by many engineers considered preferable in forming a Canal, to use the rivers in its vicinity only for the purpose of supplying the Canal with water, and not as a continuation of the inland navigation, on account of the variation in the depth of rivers from floods, or other accidents. Which of these two courses would be most expedient in the present instance, may be safely left to the determination of the engineer selected to carry out the undertaking;--it is sufficient to know that _either is practicable_, and that the expense of cutting the Canal the whole width of the isthmus would meet with a corresponding return to the undertakers. The principal difficulty anticipated in the execution of the work, arises from the unhealthiness of the climate on the Atlantic side of the isthmus--a difficulty to which the writer is by no means insensible. It has, however, been exaggerated, and by proper arrangements may be surmounted. The causes of this unhealthiness are chiefly the swampy state of the ground on the Atlantic side of the Isthmus (which the Canal itself, acting as a drain upon the surrounding country, will greatly tend to remove), and the malaria engendered by the closeness of the woods, and by the accumulation of decayed vegetable substances, which the opening of the country, incidental to the formation of the Canal now proposed, and the road afterwards adverted to, will tend to alleviate; and after all, those who have visited this part of the Isthmus, concur in stating that the mortality in the low lands about Chagres is principally owing to the imprudence of the Europeans visiting the country, in exposing themselves to the night dews by sleeping in the open air, and indulging in habits of intemperance.[8] If an association were formed for carrying out the work now projected, one of the first cares of the managers should be to erect huts or barracks for the protection of the workmen against exposure to the weather, and the appointment of a medical officer, who should be entrusted with sufficient powers to ensure obedience to his regulations.