Banneker's work with this commission was undertaken while he was still engaged in astronomical investigation, and after his services in Washington were concluded he returned to his home and resumed his work on his almanacs, which regularly appeared until 1802. He was now living alone in the home left him by his parents, and performed for himself nearly all the domestic services required for his health and comfort. Still obliged to rely mainly upon his farm for his livelihood, he tried various expedients with different tenants to rid himself of the necessity for giving so much of his time to the farm. In these efforts he was wholly unsuccessful. He finally decided, therefore, to enter into such an arrangement in the disposition of his effects as would provide him an annuity, relieving himself of all anxiety for his maintenance and at the same time affording him the leisure he wanted for study. This he was enabled to do through a contract with one of the Ellicotts, by the terms of which his friend was to take the title to Banneker's property, making the latter an annual allowance of 12 pounds for a given period of time calculated by Banneker to be the span of years he could reasonably be expected to live. Banneker was to continue to occupy and use the property during his life, after which the possession was to go to Ellicott.[173] Banneker lived, however, eight years longer than he thought he would, but Ellicott faithfully lived up to this contract. This miscalculation is said to have been the only mistake in mathematics Banneker ever made. With his domestic affairs settled to his satisfaction, and having now the desired leisure to continue his studies, he gave himself up wholly to that object.
His active mind now found time also for occasional diversion to other lines than mathematics. It was about this time that he made the calculations showing that the locust plague was recurrent in cycles of 17 years each. He also wrote a dissertation on bees which has been favorably compared with a similar contribution by Pliny on the same subject written nearly 1800 years earlier. Banneker's nature seemed tuned also to the softer notes in the song of life. He loved music, and often, as a relaxation, he would sit beneath a huge chestnut tree near his house and beguile the hours by playing on his flute or violin.[174]
The disastrous war waged in 1793 so disturbed Banneker that he devoted much time to the study of the best methods to promote peace. To this end he suggested that the United States Government establish a department in the President's cabinet to be in charge of a Secretary of Peace. He then made a strong appeal to the authorities of his government to take a broad stand based on humanity and justice and in that spirit to formulate a comprehensive plan by which A Lasting Peace[175] might be substituted for the wars that were then disturbing the world.
During these years his home was frequently visited by people who sought him because of his intellectual gifts, and who were in no wise abashed by the fact of his racial connection. To them he was merely an honored citizen in the field of achievement.[176] "During the whole of his long life," says Benjamin Ellicott, "he lived respectably and much esteemed by all who became acquainted with him, but more especially by those who could fully appreciate his genius and the extent of his acquirements. Although his mode of life was regular and extremely retired,—living alone, having never married, cooking his own victuals and washing his own clothes, and scarcely ever being absent from home,—yet there was nothing misanthropic in his character; for a gentleman who knew him thus speaks of him: 'I recollect him well. He was a brave-looking pleasant man, with something very noble in his appearance.' His mind was evidently much engrossed in his calculations; but he was glad to receive the visits which we often paid him."
Another writes: "When I was a boy I became very much interested in him, as his manners were those of a perfect gentleman: kind, generous, hospitable, humane, dignified, and pleasing, abounding in information on all the various subjects and incidents of the day, very modest and unassuming, and delighting in society at his own house. I have seen him frequently. His head was covered with a thick suit of white hair, which gave him a very dignified and venerable appearance. His dress was uniformly of superfine broadcloth, made in the old style of a plain coat, with straight collar and long waistcoat, and a broad-brimmed hat. His color was not jet-black, but decidedly negro. In size and personal appearance, the statue of Franklin at the Library of Philadelphia, as seen from the street, is a perfect likeness of him. Go to his house when you would, either by day or night, there was constantly standing in the middle of the floor a large table covered with books and papers. As he was an eminent mathematician, he was constantly in correspondence with other mathematicians in this country, with whom there was an interchange of questions of difficult solution."[177]
Mrs. Tyson describes the courtliness of his manner when receiving friendly visits from the ladies of his community, who delighted to call on him in his neat cottage, to have the pleasure of his rare conversation. On these occasions he would sometimes allude to his love of the study of astronomy as quite unsuited to a man of his class.[178]
In the earlier years of his life Banneker is said to have formed the "social drink" habit, which we can imagine was all the easier for a man of his agreeable manners, in an environment where hospitality was general, and in a day when cordiality usually expressed itself in that way. But to the credit of his strength of mind and will, it is also said that he actually overcame that habit by the mere determination that he would do it, and that on his return from his stay with the commission at Washington he is said to have declared rather proudly that he never partook once of the wines that were so freely offered him.[179]
Banneker was not a professing Christian and not an adherent of any church, but "he loved the doctrines and mode of worship of the Society of Friends, and was frequently at their meetings." A contemporary says: "We have seen Banneker in Elkridge meeting house, where he always sat on the form nearest the door, his head uncovered. His ample forehead, white hair and reverent deportment gave him a very venerable appearance, as he leaned on the long staff (which he always carried with him) in quiet contemplation."[180]
There was no blemish in the entire record of his singularly active and useful life. His whole span of years appears to have been spent with a conscience void of offense, and he approached the end with a sereneness of mind well befitting the high ideals set before him. Although his body never wandered far from the place of his birth, his mind was permitted to soar through all space and to dwell in the regions of the stars and the planets. We can never know how sorely his finer spirit grieved over the tribulations that beset his blood kinsmen in the days of their bondage in this land of their birth, but we can well believe that in the loftiness of his soul he dreamed the dream of their ultimate release.
As the shadows gathered about him towards the evening of his life he abandoned those pursuits that had brought him merited distinction, and had gained for him the admiration of a host of friends chiefly among people that the world called superior. One beautiful Sabbath afternoon, in the month of October, 1806,[181] while quietly resting in the shade of a tree beside his cottage on the brow of a hill that overlooked the Patapsco Valley he seemed to hear the voices that beckoned him to the other world. And as if stirred by some sudden impulse he rose and made an effort to walk once more along the paths that had so often been his quiet retreat in the moments of his deep reflections. He had not gone far, when his strength gave way, and he sank helpless to the ground. He was assisted back to his home by a friendly neighbor, but the noon of his day having fully merged into the evening, the dark shadows of Eternal Night settled over him.