Descartes and the Hyperbolic Quest: Lens Making Machines and Their Significance in the Seventeenth CenturyIn 1629, the natural philosopher René Descartes enticed a young artisan to undertake a secretive project, one that promised to revolutionize early modern astronomy. Descartes believed he had conceived a new kind of telescope lens, shaped by the light of reason itself, & surpassing anything ever to come from the hands of the glass-working craftsmen of the era. These novel lenses would never be touched by human hands -- they would be cut by an elaborate machine, a self-regulating & automatic device. This study traces the inception, development, & finally the collapse of this ambitious enterprise, which absorbed the energies & attentions of a broad range of 17th-century savants, including Huygens, Wren, Hevelius, Hooke, & even Newton. Illus. |
Other editions - View all
Common terms and phrases
abrasive Adam and Tannery anaclastic artisan astronomers Auzout Beaune Bedini Beeckman Besson's Cambridge Campani cartes Cartesian Caus claimed Constantijn Huygens context convex Correspondence of Descartes craft practice craftsman curve cutting D'Orleans Descartes wrote Dioptrique Oculaire Discourse on Method discussion Divini Eustachio Divini Ferrier Figure Florimond De Beaune form lathe forming pan Galileo Gaukroger geometry Giuseppe Campani glass blank grinding machine grinding wheel hand handcraft Helden Henry Oldenburg Hevelius Hooke Huygens hyperbolic doubt hyperbolic form hyperbolic lenses idea instrument makers Intellectual Biography Isaac Beeckman Kepler lens grinding machine lens makers lens making machine letter Magic of Numbers Maignan mathematical instrument mechanical lens mechanical philosophy mechanical systems Meditations Mersenne Mydorge natural philosophers Newton Oeuvres Complètes Oeuvres de Descartes optical Paris perfect plate polishing Porta precision problem promise refraction relationship Rheita savants Science Scientific Instrumentation seventeenth century shape spectacle spherical aberration spherical lenses telescope theory tion tool tradition turner Wren's
Popular passages
Page 36 - Those long chains of reasoning, simple and easy as they are, of which geometricians make use in order to arrive at the most difficult demonstrations, had caused me to imagine that all those things which fall under the cognizance of man might very likely be mutually related in the same fashion...
Page 127 - To practical mechanics all the manual arts belong, from which mechanics took its name. But as artificers do not work with perfect accuracy, it comes to pass that mechanics is so distinguished from geometry, that what is perfectly accurate is called geometrical; what is less so is called mechanical.
Page 127 - However, the errors are not in the art, but in the artificers. He that works with less accuracy is an imperfect mechanic; and if any could work with perfect accuracy, he would be the most perfect mechanic of all, for the description of right lines and circles, upon which geometry is founded, belongs to mechanics.
Page 8 - ... must have a hollow iron dish, that is a portion of a great Sphaere, as you will have your Spectacles more or less Convex; and the dish must be perfectly polished. But if we seek for Concave Spectacles; let there be an Iron-ball, like to those we shoot with Gun-powder from the great Brass Canon : the superficies whereof is two, or three foot about : Upon the Dish, or Ball there is strewed white-sand, that comes from Vincentia, commonly called Saldame, and with water it is forcibly rubbed between...
Page 128 - ... intellectu, qui jam omnes errandi causas perspexit ; non amplius vereri debeo ne illa, quae mihi quotidie a sensibus exhibentur, sint falsa, sed hyperbolicae superiorum dierum dubitationes, ut risu dignae, sunt explodendae.
Page 8 - ... lens as the object and not inverted. From the first production of lenses every kind of experiment was tried to see what could be done with them. In this period of about four centuries from the introduction of lenses to the invention of the compound microscope there was a very close alliance between to the same handle with Colophonia, and work as you did before, that on both sides it may receive a Concave or Convex superficies; then rubbing it over again with the powder of Tripolis. that it may...
Page 9 - ... thinge, a great distance, and specyally by the ayde of other glasses. [Here we have the principle of the Refracting Telescope.] . . . the smallest sorte of them, commonly called spectacle glasses . . . ys grounde vppon a toole of Iron, made of purpose, somewhat hollowe, or concave inwardes. . . . The Glasse, after that yt ys full rounde, ys made fast with syman vppon a smalle block, and so grounde by hande, vntill that yt ys bothe smoothe and also thynne, by the edges, or sydes, but thickest...
Page 8 - CoFophonia melted; and if you will make Convex Spectacles, you must have a hollow iron dish, that is a portion of a great Sphaere, as you will have your Spectacles more or less Convex; and the dish must be perfectly polished. But if we seek for Concave Spectacles; let there be an Iron-ball, like to those we shoot with Gun-powder from the great Brass Canon : the superficies whereof is two, or three foot about : Upon the...
Page 17 - According to the law of reflection the angle of incidence equals the angle of reflection and the incident ray, the reflected ray as well as the normal ray always lie in the same plane.
Page 9 - And may be made of any kynde of glasse, but the clearer the better. And so the Glasse, after that yt ys full rounde, ys made fast with syman vppon a smalle block, and so grounde by hande, vntill that yt ys bothe smoothe and allso thynne, by the edges, or sydes, but thickest in the middle.