Symbol Guide

Newton's use of alchemical symbols was creative and unorthodox. Like most alchemists, he employed the planetary symbols for the known metals, and used standard symbols for common substances such as sal ammoniac (ammonium chloride), salt of tartar (potassium carbonate), vitriol (iron and copper sulfate), and the strong acids. But in addition to these and other well known symbols, he created a multitude of additional, more personal pictograms. The easiest of these to decipher are Newton's signs for the ores of the metals. These he represents by taking the standard alchemical symbol and attaching an "o" to it for "ore." With Newton's other symbols things become much more difficult, since he does not decode these for the reader. In general, a horizontal line through a circle may be taken to indicate a salt, a cross atop a circle may indicate an antimonial compound, and the asterisk-like sal ammoniac star attached to a symbol may indicate that the chemical in question is volatile. At present the editors do not claim to have exact knowledge of the chemical referents to which most of these compound symbols correspond. Hence we have provisionally employed the terms for them supplied by Marie Boas and A. Rupert Hall in their article "Newton's Chemical Experiments," Archives internationales d'histoire des sciences, 1958, pp. 113-152. As our knowledge of Newton's chymistry deepens, the referents to these pictograms may well become known, in which case we will add them to the site.

Term Pictogram Antimony ♁ Antimony Ore 🜫 Aqua Fortis  Aqua Fortis  Aqua Regia  Aqua Regia 🜇 Aquarius ♒ Aries ♈ Bismuth (Neptune, Trident) ♆ Bismuth ore  Bismuth ore [variant] 🜾 Caduceus, sideways 🝐 Cancer ♋ Capricorn ♑ Copper (Venus) ♀ Copper antimoniate 🜥 Copper ore 🜠 Crucible 🜊 Drachm symbol ʒ Earth ♁ First quarter moon (Silver) ☽ Gemini ♊ Gold (Sun) ☉ Inverted leo  Iron ore 🜜 Iron ore [variant]  Iron ore [probable variant] 🜝 Iron ore and copper combined [probable] 🜡 Last quarter moon ☾ Lead ore 🜪 Lead (Saturn) ♄ Lead (Saturn unbarred)  Libra ♎ Leo ♌ Mars (Iron) ♂ Mercury ☿ Mercury sublimate 🜐 Mercury sublimate [variant]  Niter 🜕 Nota Bene  Oil 🝆