Silvio A. Bedini

“ For scientific instrument makers, one need only examine the nineteenth century city directories of Boston, Philadelphia and New York to find hundreds of names of craftsmen and firms. It is, to be sure, an antiquarian research, for one does not expect to find great discoveries coming from these people. But just as in Europe, it is a populous trade, influential in the growth of science and highly effective in spreading and intensifying the itch for ingenious instruments and devices. ”

“ Lying between these circles, there is another eccentric circle (black with a spot) exhibiting the shadow of the earth, in which the little moon sinks itself, carried by the lowest index. In any ecliptic full moons, the patent number of inches of immersion somehow affects the minds of the cultured, but also the scheme of maximum obscuration affects the eyes of the illiterate themselves. ”

“ Long study had not only convinced me that an automaton was within the realm of possibility, but that there were many mechanical systems by which it could be achieved. I girded myself for a new project and developed it theoretically from the ground up, but under such unhappy auspices that not only did all hope fail that anyone would ever appear who might have seemed willing to set his hand to the work, but that the new discovery itself was scoffed at by many as altogether a nightmarish delirium of an unbridled imagination. ”

“ As the increasing preoccupation with subdivision of land and with surveying led to a greater demand for suitable instruments, it was the skilled craftsmen of the community, such as the clockmaker and the silversmith, that were called upon to produce them. Superb examples also were produced by the advanced scientific men, or "mathematical practitioners," of the period.
Colonial Training in Instrument Making
One may well ask, where did these native craftsmen acquire the knowledge that enabled them to produce so skillfully the accurate [Pg 9-10] and often delicate mathematical instruments? ”

“ Metal was expensive. As evidenced in the records of Daniel Burnap, for instance, it was possible to produce surveying compasses in brass in two grades, presumably one more elaborate than the other. Yet Burnap's prices ranged between six pounds and four pounds for the metal instruments, making them still well out of reach of many of the would-be surveyors. Accordingly, Burnap—and presumably numerous other instrument makers of the period—produced from wood an economy model that sold for not more than two pounds, thus placing the item within the reach of the nonprofessional surveyor. ”

“ There is reason to believe that a few mathematical practitioners and instrument makers lived and worked in the New England colonies as early as the first century of colonization.
The evidence, frankly meager, consists of two items. The first is a reference relating to James Halsie of Boston. In a land deed made out to him in 1674 he was referred to as a "Mathematician." [2] Halsie was listed as a freeman of the Massachusetts Bay Colony in 1690. ”

“ Now it is possible for even an amateur in astronomy, sufficiently instructed, to predict for any given time not only the mean position of the planets, but also their true longitude and latitude, and even the true time of their conjunctions, and their ecliptic oppositions, with all the attendant circumstances. Yet, until now, no hypothesis has been devised which would force an automaton to show to us, before our very eyes, the eclipses of the planets in their true and certain times. ”

“ Thus, the need for practical mathematical instruments for the surveyor and navigator became critical in proportion to the need for men to make and use them, and it is not surprising to discover that the majority of the instruments produced and advertised by early American makers were for surveying, with nautical instruments in second place. Generally, the surveyors were not professionals; they were farmers, tradesmen, or craftsmen with a sound knowledge of basic arithmetic and occasionally with some advanced study of the subject as taught in the evening schools. ”

“ Do not, however, expect, star-loving reader, that here anything at all that you may wish can be drawn forth as from its source, for to demand this would be almost the same as to seek to drain as from a cup all the vast knowledge of the many arithmetical sciences from the narrow confines of one book. You will understand how impossible that is when, through prolonged labor, you have grown somewhat more mature in this kind of learning. ”

“ It is possible to see in public collections, for instance, a Davis quadrant of English manufacture exhibited beside a later example, signed by a New England maker, which comes extraordinarily close to duplicating it in every feature.
As with the presumed influence of published works, the practice of copying imported instruments cannot be documented, but it must have been engaged in by many of the unschooled New England instrument makers. By this means some may even have profited to the degree that they became professional craftsmen without benefit of formal apprenticeship. ”

“ What has been said about the true new moon is to be understood also, proportionately, about the true full moon. For when, with respect to the equations of the centers, the moon shall be distant on the mechanism by a full semicircle from the sun (also in the heavens it will be truly in opposition to the sun) there will be a true full moon. ”

“ Within recent years fairly exhaustive studies have been made on many aspects of American science and technology. For example, there have been numerous works relating to clocks and clockmakers, so that the collector and horological student have a number of useful sources on which to rely. More recently there has been a series of publications on the development of American tools and their makers. Until now, however, no systematic study has been attempted of the scientific instruments used in the United States from its colonial beginnings. ”

“ The evolution of its design by Father Francesco Borghesi and the building of the complex mechanism devised by the clockmaker, Bartolomeo Antonio Bertolla, is a story of the vision of one man turned into reality by another. The result of their collaboration is the unique, astronomical timepiece now in the Museum of History and Technology. ”

“ It can be surmised, therefore, that surveying instruments, as well as instruments for other purposes, were produced in both brass [Pg 69] and wood simultaneously by many of the New England makers in order to provide suitable instruments in a flexible price range to meet the demands of the trade. Whereas today modern manufacturing methods make it possible to produce instruments in a wide variety, both in quality and price, to suit the needs and capabilities of every prospective purchaser, the production facilities of the 18th century were much more limited. ”

“ Some attained by more, some by less, but all by some degree of wandering from the truth, either worn out by the intricacies of the motions, or deceived and deceiving by the errors of their calculations. This fact those well know, who, setting about to collect information of this kind, even those publicized not long ago, with true astronomical calculation, have been bored to death while digging out by the most elementary and superficial arithmetical torture, the worst of fallacies spontaneously erupting from thence. ”

“ Of equal interest is a large semicircumferentor made by an unknown American instrument maker in the second half of the 18th century. The instrument (fig. 34) consists of a plate of hammered brass attached to a quarter circle block of mahogany, with a glass covered trough compass within a silvered opening, and the gradations stamped into the brass. The brass sighting bars are attached to a swivelling bar that can be fixed in place with a set screw underneath the block. The instrument, which is in the collection of the writer, is not signed with a maker's name. ”

“ Nay, further, even this little work itself can be improved on and surpassed by new inventions. Otherwise that other old adage, almost as old as the world, would prove false, "What you have found already done, you can easily repeat, nor is it difficult to add to what has already been invented." ”

“ Benjamin Banneker
A name that is too often ignored in the history of science in colonial America is that of a free Negro, Benjamin Banneker (c. 1734-1806) of Baltimore. A farmer by occupation, Banneker was the son of a native African slave and a free mulatto woman. In his spare time he attended the school of a Quaker farmer; the only book he owned was the Bible. When he was a young man he acquired a watch from a trader, and from it he developed his love of science and instruments. ”

“ But, from the technical point of view, it should be noted that those craftsmen who produced clocks and instruments and did not have their own brass foundries probably found that a good piece of straight-grained hardwood was as stable for holding its dimensions with the grain as a piece of brass. Shrinkage was at right angles to the grain; hence, for fixed linear stability wood was as good as brass. For rigidity per unit weight, wood was better than brass; and for availability and ease of working, wood was superior to brass. ”

“ On Christmas Day, 1785, Gurdon was married in New London to Temperance Williams of Groton. In 1789 their first child, Marvin, was born, and in October of the same year the Huntingtons moved from Windham to Walpole, New Hampshire. No reason can be found for the move, other than the possibility that Gurdon might have anticipated greater opportunity in the new community. There he applied himself to his trade as goldsmith and clockmaker, but apparently he was not very successful. His family grew, and by the time of his death there were eight children. ”

“ In the days when the 'bounds' of great wilderness tracts were being marked off by deep-cut blazes in the trees along a line, a knowledge of land surveying was a useful skill, and many a boy learned its elements by following the 'boundsgoer' in his work of 'running the line.' And those who did not actually take part in running the line must have attended many a gay springtime 'processioning' when neighbors made a festive occasion out of 'perambulating the bounds'. ”