1862 – De Chancourtois' Telluric Screw

The French geologist Alexandre-Émile Béguyer de Chancourtois was the first scientist to see the periodicity of elements when they were arranged in order of their atomic weights. Credited with being the original discoverer of the periodicity of elements and the originator of the three-dimensional method of element arrangement and representation. He drew the elements as a continuous spiral around a metal cylinder divided into 16 parts. The atomic weight of oxygen was taken as 16 and was used as […]

The French geologist Alexandre-Émile Béguyer de Chancourtois was the first scientist to see the periodicity of elements when they were arranged in order of their atomic weights. Credited with being the original discoverer of the periodicity of elements and the originator of the three-dimensional method of element arrangement and representation. He drew the elements as a continuous spiral around a metal cylinder divided into 16 parts. The atomic weight of oxygen was taken as 16 and was used as the standard against which all the other elements were compared. Tellurium was situated at the centre, prompting vis tellurique, or telluric screw. Despite de Chancourtois' work, his publication attracted little attention from chemists around the world. The reason being that De Chancourtois's original diagram was left out of the publication, making the paper hard to comprehend. The paper also dealt mainly with geological concepts, and did not suit the interests of many chemistry experts. It was not until 1869 that Dmitri Mendeleyev's periodic table attracted attention and gained widespread scientific acceptance. The original (unique) telluric screw is now hosted at the museum de l'École des Mines. Sources: Jacques Touret "Dans l'ombre de ses maîtres", Travaux Du comité Français d'histoire de la géologie - Troisième série - T.XX (2006) Science and Society picture library All periodic tables website Wikipedia article on Alexandre-Émile Béguyer de Chancourtois

Added by: Fanny Chevalier. Category: Uncertain Tags: chemistry, periodic table, telluric screw

1865 – Hofmann's Croquet Ball Models

August Wilhelm Hofmann was the first to introduce physical representations of molecules into lectures during his Friday Evening Discourses presentation "On the Combining Power of Atoms" at London's Royal Institution of Great Britain in . He introduced a colored set of four croquet balls to represent atoms (hydrogen, oxygen, chlorine and nitrogen), implanted with a fixed number of sticks corresponding to each atom's valence. Thus we distinguish the chlorine atom as univalent, the atom of oxygen […]

August Wilhelm Hofmann was the first to introduce physical representations of molecules into lectures during his Friday Evening Discourses presentation "On the Combining Power of Atoms" at London's Royal Institution of Great Britain in . He introduced a colored set of four croquet balls to represent atoms (hydrogen, oxygen, chlorine and nitrogen), implanted with a fixed number of sticks corresponding to each atom's valence. Thus we distinguish the chlorine atom as univalent, the atom of oxygen as bivalent, that of nitrogen as trivalent, and lastly the carbon atom as quadrivalent. - this I believe I can show you by a very simple contrivance. I will on this occasion, with your permission, select my illustration from that most delightful of games croquet. Let the croquet balls represent our atoms, and let us distinguish the atoms of different elements by different colours. The white balls are hydrogen, the green ones chlorine atoms; the atoms of fiery oxygen are red, those of nitrogen, blue; the carbons atoms, lastly, are naturally represented by black balls. But we have, in addition, to exhibit the different combining powers of these atoms. This we accomplish by screwing into the balls a number of metallic arms (tubes and pins), which correspond respectively to the combining powers of the atoms represented, and which, while constituting an additional feature of distinction, enable us at the same time to join the balls and to rear in this manner a kind of mechanical structures in imitation of the atomic edifices to be illustrated." (Extracts from Proceedings of the Royal Institution, 4, 401-430) Interestingly, while physical representations, Hofmann had the models built so that they were two-dimensional representations of molecules. It's only in the mid 70s that 3-dimensional models emerged. Sources: J. Michael McBride Models and Structural Diagrams in the 1860s Wikipedia August Wilhelm von Hofmann

Added by: Fanny Chevalier. Category: Uncertain Tags: chemistry, education, molecules, pragmatic, science

1866 – Dewar's Brass Strip Models

Mechanical arrangement adapted to illustrate structure in the non-saturated hydrocarbons by the chemist James Dewar. The model is made of bars, clamped together so as to allow free motion. In order to make the combination look like an atom, a thin round disc of blackened brass can be placed under the central nut. At the ends of the arms are holes to connect one carbon atom with another by means of a nut. The structure at the bottom right of his figure is now called "Dewar benzene". I bring […]

Mechanical arrangement adapted to illustrate structure in the non-saturated hydrocarbons by the chemist James Dewar. The model is made of bars, clamped together so as to allow free motion. In order to make the combination look like an atom, a thin round disc of blackened brass can be placed under the central nut. At the ends of the arms are holes to connect one carbon atom with another by means of a nut. The structure at the bottom right of his figure is now called "Dewar benzene". I bring before the Society a simple mechanical arrangement adapted to illustrate structure in the non-saturated hydrocarbons. This little device is the mechanical representative of Dr. C. Brown's well-known graphic notation. A series of narrow thin bars of brass of equal length are taken, and every two of the bars clamped in the centre by a nut, so as to admit of free motion the one on the other. Such a combination represents a single carbon atom with its four places of attachment. In order to make the combination look like an atom, a thin round disc of blackened brass can be placed under the central nut. At the ends of the arms are holes to connect one carbon atom with another by means of a nut. The filling up of the places of attachment may be effected by slipping on the arms round discs of brass having a groove attached, and placing the symbol of the chemical element on the round projection. A carbon atom would then look like the following diagram. By J. Dewar, Esq. (from Proceedings of the Royal Society of Edinburgh, VI, Session 1866-67, pp. 82-86) Dewar sent Kekulé his brass strip molecular modeling kit in 1866, and Kekulé used it to hypothesize possible molecular structures for compunds. In 1867, Kekulé used Dewar's models to come up with a reasonable (by today's standards) structure for mesitylene (1,3,5-trimethylbenzene, C9H12). Note that in the drawing, little dots appear in in the middle of some of the bonds. They appear because the drawings are of a real model, and the various atoms were screwed together at the dots. Also note that the acetone molecules in the model appear not to be symmetrical, with one C-C bond bent and the other one straight. However, the bent bond is only an illusion created by the flatness of the paper; in Kekuleé's 3-D model, all of the C-C bonds are straight. James Deward is famous for his Researches in low temperature phenomena. See [3] to learn more. Sources: J. Michael Mc Bride Models and Structural Diagrams in the 1860s J. Dewar, Esq., Proceedings of the Royal Society of Edinburgh, VI, Session 1866-67, pp. 82-86 Today in Science History website

Added by: Fanny Chevalier. Category: Uncertain Tags: chemistry, discovery, molecules, science

1875 – Van't Hoff's Molecular Paper Models

Van’t Hoff disseminated his stereochemical ideas to leading chemists of the day by sending them 3-D paper models of tetrahedral molecules, like these now housed in the Leiden Museum. There might be some difficulty in following my reasoning. I felt this myself, and I have made use of cardboard figures to facilitate the representation. Not wanting to require too much of the reader I will gladly send him the complete collection of all these objects Sources: Van der Spek, Trienke M. Selling a […]

Van’t Hoff disseminated his stereochemical ideas to leading chemists of the day by sending them 3-D paper models of tetrahedral molecules, like these now housed in the Leiden Museum. There might be some difficulty in following my reasoning. I felt this myself, and I have made use of cardboard figures to facilitate the representation. Not wanting to require too much of the reader I will gladly send him the complete collection of all these objects Sources: Van der Spek, Trienke M. Selling a Theory: The Role of Molecular Models in JH van't Hoff's Stereochemistry Theory. Annals of science 63.02 (2006): 157-177. Gross Ari, Form and Function: Seeing, Knowing, and Reasoning with Diagrams in the Practice of Science, 2013. PhD Thesis. University of Toronto Chemical Heritage Foundation website Image courtesy O. Bertrand Ramsay

Added by: Fanny Chevalier. Category: Uncertain Tags: chemistry, paper, science, tetrahedral molecules

1898 – Crookes' Vis Generatrix

Model of Crookes’ "Vis Generatrix" made in 1898, built by his assistant, Gardiner. From: Proc. R. Soc. Lond. 63, 408. The vertical scale represents the atomic weight of the elements from H = 1 to Ur = 239. Missing elements are represented with a white circle. Similar elements appear underneath each other. With this model, Crookes was trying to visualize the hypothetical relationship between various elements in three dimensions. See all the other entries with the tag "periodic table" to see […]

Model of Crookes’ "Vis Generatrix" made in 1898, built by his assistant, Gardiner. From: Proc. R. Soc. Lond. 63, 408. The vertical scale represents the atomic weight of the elements from H = 1 to Ur = 239. Missing elements are represented with a white circle. Similar elements appear underneath each other. With this model, Crookes was trying to visualize the hypothetical relationship between various elements in three dimensions. See all the other entries with the tag "periodic table" to see other historical examples. Sources: Handbook on the Physics and Chemistry of Rare Earths, Volume 41 page 45. "Types of graphic classifications of the elements. III. Spiral, helical, and miscellaneous charts." Journal of Chemical Education 11, no. 5 (1934): 288. Principles of General Chemistry, made available by Andy Schmitz (lardbucket.org). Chapter 7 - The Periodic Table and Periodic Trends

Added by: Fanny Chevalier. Category: Passive physical visualization Tags: chemistry, crooke, generatrix, periodic table

1940s – Stedman's 3D Periodic Table

Dr. Don Stedman from the National Research Council Canada designed this 3-D periodic table in the 1940s. Stedman considered many factors and characteristics of the elements as he designed his models. While in this model all the usual groups of elements are found, changes from one group to another are also represented, and their origins are more easily understood. Stedman believed that his model gave more insight into “the orderly development and classification of the elements.” Source: Canada […]

Dr. Don Stedman from the National Research Council Canada designed this 3-D periodic table in the 1940s. Stedman considered many factors and characteristics of the elements as he designed his models. While in this model all the usual groups of elements are found, changes from one group to another are also represented, and their origins are more easily understood. Stedman believed that his model gave more insight into “the orderly development and classification of the elements.” Source: Canada Science and Technology Museum, CSTMC/SMSTC – 1995.0335

Added by: Devon Elliott. Category: Passive physical visualization Tags: chemistry, periodic table, science

1945 – Electron Density Map and Molecular Model of Penicillin

Electron density map and model of Penicillin created by Dorothy Crowfoot Hodgkin in 1945 based on her work on X-ray crystallography. The Penicillin molecule was the first molecule whose structure was derived entirely from X-ray data. Dorothy Hodgkin later received the Nobel price for applying the same technique to determine the structure of the B12 molecule. Dorothy Hodgkin (1910-94) was awarded the prestigious and exclusive Order of Merit in 1965 to add to her 1964 Nobel Prize for ”her […]

Electron density map and model of Penicillin created by Dorothy Crowfoot Hodgkin in 1945 based on her work on X-ray crystallography. The Penicillin molecule was the first molecule whose structure was derived entirely from X-ray data. Dorothy Hodgkin later received the Nobel price for applying the same technique to determine the structure of the B12 molecule. Dorothy Hodgkin (1910-94) was awarded the prestigious and exclusive Order of Merit in 1965 to add to her 1964 Nobel Prize for ”her determinations by X-ray techniques of the structures of important biochemical substances”. The Order of Merit is a group of 24 individuals of great achievement in the fields of the arts, learning, literature and science. Hodgkin was only the second woman to be part of the exclusive group - the first was Florence Nightingale. Sources: Hodgkin, Dorothy Crowfoot: The X-ray analysis of complicated molecules. Nobel Lecture, December 11, 1964. Image source: Science Museum, London. Blog of the Science Museum, London.

Added by: Yvonne Jansen. Category: Passive physical visualization Tags: chemistry, crystallography, electron model, penicillin, science

1947 – Dorothy Hodgkin's Electron Density Contours

Nobel prize winning crystallographer Dorothy Crowfoot Hodgkin created another physical visualization in the mid 1940's, showing part of the structure of penicillin. An original of this artifact is in the Oxford Museum of the History of Science. This technique recently inspired artist Angela Palmer for her glass portraits. Sources: Lachlan Michael and David Cranswicka (2008) Busting out of crystallography's Sisyphean prison: from pencil and paper to structure solving at the press of a button: […]

Nobel prize winning crystallographer Dorothy Crowfoot Hodgkin created another physical visualization in the mid 1940's, showing part of the structure of penicillin. An original of this artifact is in the Oxford Museum of the History of Science. This technique recently inspired artist Angela Palmer for her glass portraits. Sources: Lachlan Michael and David Cranswicka (2008) Busting out of crystallography's Sisyphean prison: from pencil and paper to structure solving at the press of a button: past, present and future of crystallographic software development, maintenance and distribution. Oxford Museum of the History of Science. Model of the Structure of Penicillin, by Dorothy Hodgkin, Oxford, c. 1945.

Added by: Pierre Dragicevic, sent by: Jean-Baptiste Labrune. Category: Passive physical visualization Tags: chemistry, crystallography, penicillin, science

1953 – Watson and Crick's 3D Model of DNA

In 1953, James Watson and Francis Crick suggested what is now accepted as the first correct double-helix model of DNA structure in the journal Nature. Their double-helix, molecular model of DNA was then based on a single X-ray diffraction image taken by Rosalind Franklin and Raymond Gosling in May 1952, as well as the information that the DNA bases are paired. Experimental evidence supporting the Watson and Crick model was published in a series of five articles in the same issue of Nature. Of […]

In 1953, James Watson and Francis Crick suggested what is now accepted as the first correct double-helix model of DNA structure in the journal Nature. Their double-helix, molecular model of DNA was then based on a single X-ray diffraction image taken by Rosalind Franklin and Raymond Gosling in May 1952, as well as the information that the DNA bases are paired. Experimental evidence supporting the Watson and Crick model was published in a series of five articles in the same issue of Nature. Of these, Franklin and Gosling's paper was the first publication of their own X-ray diffraction data and original analysis method that partially supported the Watson and Crick model; this issue also contained an article on DNA structure by Maurice Wilkins and two of his colleagues, whose analysis supported their double-helix molecular model of DNA. In 1962, after Franklin's death, Watson, Crick, and Wilkins jointly received the Nobel Prize in Physiology or Medicine. Sources: Image from thehistoryblog.com. Text from Wikipedia.

Added by: Paulie D. Category: Uncertain Tags: chemistry, dna, nobel, science

1957 – Proteine Visualizations

Left image: The very first physical model of a protein (myoglobin) built by crystallographer John Kendrew in 1957 using plasticine. The image is from a 1958 Nature article, for a more recent photo see here. In 1960 Kendrew completed a higher-resolution skeletal model known as the "forest of rods". The model was 2-meter wide, made of brass, and supported with 2,500 vertical rods, making it barely legible. Colored clips were attached to the rods to visualize electron density. See photos here and […]

Left image: The very first physical model of a protein (myoglobin) built by crystallographer John Kendrew in 1957 using plasticine. The image is from a 1958 Nature article, for a more recent photo see here. In 1960 Kendrew completed a higher-resolution skeletal model known as the "forest of rods". The model was 2-meter wide, made of brass, and supported with 2,500 vertical rods, making it barely legible. Colored clips were attached to the rods to visualize electron density. See photos here and here. Middle image: Biochemist Max Perutz working on a model of hemoglobin similar to the "forest of rods", completed in 1968. Hemoglobin is made of 10,000 atoms. Perutz and Kendrew shared the 1962 Nobel Prize in Chemistry for working out the structure of those giant molecules. Right image: A visualization device built by biochemist Fred Richards in 1968 and known as the "optical comparator", the "Richards Box" or "Fred's Folly". This device taller than a person used a half-silvered mirror to optically combine a wireframe physical protein model with electron density maps. Sources: Eric Martz and Eric Francoeur (1997-2004) History of Visualization of Biological Macromolecules. Michael L. Connolly (1996) Molecular Surfaces: A Review Jeremy Norman's History of Science.com Online Bookshop Emily Candela (2012) Assembling an aesthetic. Protopedia entry on Frederic Richards Video interview wit Max Perutz (see 14:20 to see one of the physical models and hear him talk about how physical models affected the way he looked at his work).

Added by: Pierre Dragicevic. Category: Passive physical visualization Tags: chemistry, hemoglobin, Perutz, proteine, science

1970 – Byron's Bender

In the early 1970's, crystallographer Byron Rubin invented a tool that bends wires to make proteins models. The tool was popular until the 1990s. Byron Rubin became an artist who builds large-scale molecular sculptures. Eric Martz and Eric Francoeur explain how such physical models yielded important scientific insights: An example illustrating the importance of models from Byron's Bender occurred at a scientific meeting in the mid 1970's. At this time, less than two dozen protein structures had […]

In the early 1970's, crystallographer Byron Rubin invented a tool that bends wires to make proteins models. The tool was popular until the 1990s. Byron Rubin became an artist who builds large-scale molecular sculptures. Eric Martz and Eric Francoeur explain how such physical models yielded important scientific insights: An example illustrating the importance of models from Byron's Bender occurred at a scientific meeting in the mid 1970's. At this time, less than two dozen protein structures had been solved. David Davies brought a Bender model of an immunoglobulin Fab fragment, and Jane and David Richardson brought a Bender model of superoxide dismutase. While comparing these physical models at the meeting, they realized that both proteins use a similar fold, despite having only about 9% sequence identity. This incident was the first recognition of the occurrence of what is now recognized as the immunoglobulin superfamily domain in proteins that are apparently unrelated by sequence. The insight was published in a paper entitled "Similarity of three-dimensional structure between the immunoglobulin domain and the copper, zinc superoxide dismutase subunit" ( Richardson et al., J. Mol. Biol. 102:221-235, 1976). Also see the more recent DIWire device by Pensalabs. Sources: Byron Rubin. molecularsculpture.com. Eric Martz and Eric Francoeur (1997-2004) History of Visualization of Biological Macromolecules. Left image from molecularsculpture.com. Right image from The Journal of Biocommunication.

Added by: Pierre Dragicevic. Category: Enabling technology Tags: chemistry, molecule, protein, science, wire bender

1995 – San Diego TeleManufacturing Facility

In 1995, Mike Bailey from the San Diego Supercomputer Center created the SDSC TeleManufacturing Facility to help scientists visualize their data in physical form. In 1997, the facility produced one of the first digitally-fabricated molecular models using laminated object manufacturing. The biochemists involved in the project got insights that they were not able to get from the on-screen 3D models, and concluded that: modern physical models are important tools that significantly extend the […]

In 1995, Mike Bailey from the San Diego Supercomputer Center created the SDSC TeleManufacturing Facility to help scientists visualize their data in physical form. In 1997, the facility produced one of the first digitally-fabricated molecular models using laminated object manufacturing. The biochemists involved in the project got insights that they were not able to get from the on-screen 3D models, and concluded that: modern physical models are important tools that significantly extend the understanding of protein assembly available from modern three-dimensional computer graphical analysis. Later, the TeleManufacturing Facility moved to Oregon State University, still under the direction of Mike Bailey. It was renamed the Center for Visualization Prototypes, then the Center for 3D Hardcopy. It now employs a ZCorp Z406 3D printer. The center has fabricated more than 1,000 physical models, helping scientists from many different disciplines visualize their data. Images from left to right: molecular docking, ripple model, waterless globe with exaggerated relief, human head, different mathematical curvatures on identical surface shapes. Sources: Bailey et al (1998). The use of solid physical models for the study of macromolecular assembly. Kathy A. Svitil (1998). A Touch of Science. Bailey (2005). Layered manufacturing for scientific visualization. (free author version) Bailey (2005). Center for 3D Hardcopy.

Added by: Pierre Dragicevic. Category: Passive physical visualization Tags: 3d printing, chemistry, digital fabrication, laminated object manufacturing, rearrangeable, science, scientific visualization

2004 – Scripps' Molecule Models

Since 2004 the Molecular Graphics Laboratory at the Scripps Research Institute has been making heavy use of 3D-printed full-color physical molecule models, some of which are articulated (left image), flexible (middle image), and even self-assembling (right image, see video). They also publish augmented reality systems that use those physical models. Also see our entry 1995 – SDSC TeleManufacturing Facility. Sources: Web Page: http://mgl.scripps.edu/projects/tangible_models Tommy Toy (2011) How […]

Since 2004 the Molecular Graphics Laboratory at the Scripps Research Institute has been making heavy use of 3D-printed full-color physical molecule models, some of which are articulated (left image), flexible (middle image), and even self-assembling (right image, see video). They also publish augmented reality systems that use those physical models. Also see our entry 1995 – SDSC TeleManufacturing Facility. Sources: Web Page: http://mgl.scripps.edu/projects/tangible_models Tommy Toy (2011) How Arthur Olson's Molecular Graphics Lab at Scripps is Using 3D Printing and Augmented Reality to Design Better Drugs. Alexandre Gillet et al (2004) Computer-Linked Autofabricated 3D Models For Teaching Structural Biology.

Added by: Pierre Dragicevic. Category: Passive physical visualization Tags: 3d printing, chemistry, digital fabrication, molecules, physical computation, rearrangeable, science, self-assembling

2005 – Molecular Jewellery

Raven Hanna got her PhD in biochemistry in 2000, and five years later, she became an artist and started to create jewelry based on molecular structures in order to communicate science through art. Image above: endorphine necklace. Sources: Raven Hanna www.madewithmolecules.com (see 2005 version) Leigh Krietsch Boerner (2010) Profile: Molecular Jewelry Design

Added by: Pierre Dragicevic. Category: Uncertain Tags: chemistry, data jewellery, Jewelry, molecules

2010 – Quipu of the Periodic Table

As a result of bringing together each pair of periods in a single function or binod, the author has found a new regular on the subject, which has been defined as a new quantum number, since the number of orders or regulations binod growth elements in the table, under the appearance of pairs of new types of quantum structures or periods whose organization responds to a simple mathematical function: a parable of the type Y = 4 X ^ 2 - In this case report: a) That the strings correspond to pairs […]

As a result of bringing together each pair of periods in a single function or binod, the author has found a new regular on the subject, which has been defined as a new quantum number, since the number of orders or regulations binod growth elements in the table, under the appearance of pairs of new types of quantum structures or periods whose organization responds to a simple mathematical function: a parable of the type Y = 4 X ^ 2 - In this case report: a) That the strings correspond to pairs of periods or binod and knots are double for items with orbital s (in red), six nodes for p in orange, 10 yellow d knots and 14 knots for green f . b) That in each binod or rope, appear regularly in pairing mode or dual, new quantum or orbital structures, such as moving from within the orbital previous binod. See also the entry on Peruvian Quipus, and all entries with the tag "periodic table" for historical examples of physical representations of the periodic table. Sources: Ing. Julio Antonio Gutiérrez Samanez (2010) Khipu de la tabla periodica de los elementos químicos. The internet database of periodic tables.

Added by: Fanny Chevalier. Category: Passive physical visualization Tags: chemistry, periodic table, quipus

2012 – A Soft and Transparent Handleable Protein Model

This report demonstrates the viability of a new handleable protein molecular model with a soft and transparent silicone body similar to the molecule’s surface. A full-color printed main chain structure embedded in the silicone body enables users to simultaneously feel the molecular surface, view through the main chain structure, and manually simulate molecular docking. The interactive, hands-on experience deepens the user’s intuitive understanding of the complicated 3D protein structure and […]

This report demonstrates the viability of a new handleable protein molecular model with a soft and transparent silicone body similar to the molecule’s surface. A full-color printed main chain structure embedded in the silicone body enables users to simultaneously feel the molecular surface, view through the main chain structure, and manually simulate molecular docking. The interactive, hands-on experience deepens the user’s intuitive understanding of the complicated 3D protein structure and elucidates ligand binding and protein–protein interactions. Also see our entry 2004 – Scripps’ Molecule Models or all our entries on chemistry. Sources: Masaru Kawakamia (2012) A soft and transparent handleable protein model. TCT Magazine (2012) Transparent, handleable 3D printed molecular models. Left photo by Masaru Kawakami, published by TCT Magazine.

Added by: Pierre Dragicevic, sent by: Fanny Chevalier. Category: Enabling technology Tags: 3d printing, chemistry, proteine model