On 7th Feb this year Mark Lorch, a chemist and science communicator at the University of Hull, had the idea to start an element association game. Could a determined bunch of Twitter chemists find a path through all 118 elements of the periodic table in honour of Periodic Table Day and the International Year of the Periodic Table?

It turned out that they could! #ElementTales started with mendelevium, and meandered — avoiding a few forks — all the way to gadolinium. Some of the links are funny, some are tenuous, and a lot refer to fascinating bits of chemistry trivia.

It seemed a shame not to preserve the final thread somehow. Each of the entries below is headed with a link to the original tweet — just in case you’d like to find, and follow, the thread yourself.

Without further ado, we present to you…

A meandering stroll around 118 elements

@Mark_Lorch
Hey #chemtwitter folks! Who’s up for an element association game for #PeriodicTableDay in #IYPT2019. The rules: I’ll start with an element, you reply with a story/factoid that links it to another element and so on… No repeats! #elementTales

An atom of Mendelevium, atomic number 101 (from Wikimedia Commons)

@Mark_Lorch
It’s only fitting to start with number 101 Mendelevium

@Sciencenotscary
Mendeleev designed the first periodic table, which contains every other element, including <spins random number generator> #52, tellurium <blink> I swear that was random.

@Stare_at_Air
That feels a bit like cheating! But tellurium was first discovered in gold ore from Zlatna (a Romanian town named after the Slavic term for gold).

@RyeSci
Gold is one of those lovely elements known to the ancients with a symbol accordingly, Au. My favourite of those is Mercury, Hg from Hydrargyrium or liquid silver Hg.

@chronicleflask
Mercury has a v low MP because its electronic config, [Xe] 5d¹⁰ 6s², has all full shells — so it doesn’t form the +ve metal ions & delocalised electrons bonding system as other metals. Also quantum. Zn (zinc) has a low MP for the same reason.
(Side note: see this article for more info on mercury’s liquidity https://www.chemistryworld.com/news/relativity-behind-mercurys-liquidity/6297.article)

@allisontau
Zinc is element 30. Zinc rhymes with sink. If your kitchen sink is broken you call a plumber. Plumbers are called plumbers after plumbum, the Latin word for the element lead (Pb), because the Romans used lead to make pipes.

@Mark_Lorch
Lead in Greek is μολυβδος – Molyvdos which gives use the name of element 42, molybdenum.

@chronicleflask
Molybdenum-containing enzymes are found in bacteria: the simplest and oldest of the living organisms. Living organisms on planet Earth have carbon-based biology. (Time for some non-metals, I thought!)

@Stare_at_Air
This could be taken in so many directions based on carbon‘s chemistry, but I’ll ruin it — carbon reminds me of “Carboniferous”, which sounds like it should have something to do with iron (it doesn’t).

@sciencenotscary
Iron is in the same column of the periodic table as ruthenium, which usually means it should have similar reactivity and chemical behaviour, but it turns out iron is actually completely useless as a catalyst and will not get you a PhD.

@SuperScienceGrl
I’ve had a couple of people mistake my cat’s name, RuPhos, for something to do with ruthenium – it really isn’t, it’s a phosphorus ligand.

@Mark_Lorch
Phosphorus was first extracted from urine by Hennig Brandt in 1669. Later is was discovered that bone is calcium phosphate, which made for a ready supply to feed the match industry.

@David_S_Bristol
Calcium and phosphorous combine in bone along with a substantial amount of magnesium. ~60% of magnesium in the body is in bone. It is essential for a healthy skeleton and reduced magnesium is linked to osteoporosis.

@Stare_at_Air
Magnesium is a key component of Grignard reagents. Grignard shared his Nobel Prize with Sabatier, who in turn received it for his method of hydrogenating organic compounds. Hydrogen.

@drdelusional
Hydrogen, the lightest element, forms the majority of the mass of the Universe. This odorless and tasteless gas combines with Fluorine to result in hydrogen fluoride, a highly reactive acid.
(Side note: corrosive, not (especially) reactive.)

@WildCation
Electronegativity generally increases from left to right across a period, and generally decreases from top to bottom. Fluorine is the most electronegative element on the Pauling electronegativity scale. The LEAST electronegative element is (probably) caesium.

@chronicleflask
Ooh, ooh: Robert Bunsen (he of the burner) and Gustav Kirchhoff discovered two alkali metals, cesium and rubidium, in 1860.

@Stare_at_Air
Rubidium is one of several elements named after a colour (in this case the red lines seen in the emission spectrum), but chromium is associated with so many different colours it’s just named after the Greek word for colour, χρῶμα.

@Mark_Lorch
Amongst the Terracotta warriors were found what appears to be chrome (chromium) plated bronze swords. The alloy was mostly copper and tin, but also contained magnesium, nickel and cobalt.

@sumants
Cobalt is named from ‘kobold’, German for ‘goblin’. This comes from German miners – who were harvesting (cobalt) blue pigments – naming ores ‘goblin ores’ due to the effects of arsenic poisoning when the ores were smelted.

@WildCation
The use of Scheele’s Green, a popular green arsenic-based pigment, caused poisonings in the 19th century from its use in wallpaper, candles, even food. Similarly, in the 1920s, the “Radium Girls” developed cancer from painting watch faces with radium-based pigment.

@Mark_Lorch
Radium was discovered by Marie and Pierre Curie when they extracted it from Uraninite ore. From the same ore they extracted another element which they initially called radium-F. Later Marie renamed if after her home country – Poland. Giving us … Polonium.

@Stare_at_Air
I think the f-block is feeling a bit unloved, so let’s go from the elements that the Curies discovered (Polonium) to the one named after them. Curium.

@ndbrning
Curium is (possibly) the heaviest naturally occurring element (see here: https://www.nature.com/articles/s41557-018-0190-9). The other possible candidate is plutonium.

@Stare_at_Air
Plutonium was indirectly named by a child (the name Pluto for the planet was suggested by an 11-year-old girl). The only other element named by a child is neon, suggested by Ramsay’s son.

@Mark_Lorch
William Ramsay (neon) was also the first person to isolate helium. Prior to this is was known to exist from the spectra of the Sun. Hence the element’s name from Helios… Helium.

@DrMLHarris
Inhaling helium makes your voice squeaky. What happens if you inhale xenon? Researchers at a prestigious US lab decided to find out. Turns out, “heavier than air”=”too heavy for lungs to expel”. The experimenter’s life was saved when he stood on his head.
(Side note: watch what happened when Dr Bunhead of Brainiac tried the same thing.)

@FioraAeterna
Xenon is a really unusual element. In fact, it’s the only pure element that is also a general anesthetic! Yet it’s an unreactive noble gas. Weird, huh? For weird reasons, both Xenon and Argon are now on the anti-doping banned chemicals list.

@Stare_at_Air
People are often surprised to find that the third most abundant gas in the Earth’s atmosphere is Argon. Perhaps similarly surprising is that the third most abundant element in the universe as a whole (at least as far as we know) is oxygen.

@Mark_Lorch
Oxygen is a paramagnetic. If you condense some (it’s a beautiful pale blue liquid) and then place a neodymium magnet above the surface the oxygen jumps up onto the magnet. https://www.youtube.com/watch?v=bQKVt27SUR0&feature=youtu.be&t=91

@sumants
Neodymium was originally mined as a twinned material known as didymium. Carl Auer von Welsbach fractionally distilled didymium to isolate neodymium (new twin) and the other “green twin”, praesodymium.

@Stare_at_Air
“Green twin” in Greek (πράσινος and δίδυμος) is the base for the name of praseodymium — meanwhile “green twig” in Greek (θαλλός) is the base for the name of thallium, after the bright green spectral line used to identify it.

@sumants
Thallium was extremely popular as a poison in the early 20th century, but it’s mostly banned today. As a rat poison, it worked because it inhibited proteins that contained cysteine, an amino acid that contains… Sulphur.

@ndbrning
Sulfur is responsible for the tarnishing of silver. The black tarnish is silver sulfide, caused by the metal’s reaction with small amounts of hydrogen sulfide in the air.

@Mark_Lorch
To clean your silver spoons put them in hot water with bicarb of soda & aluminium foil. The bicarb removes the aluminium oxide layer. This leaves the aluminium free to react with the silver sulfide, giving aluminium sulfide & clean silver.

@Stare_at_Air
What is still often called “tin foil” is nowadays almost always made from alumin(i)um. But it used to be made exclusively from tin until the early 20th century (first Al foil came around in 1910, but it took a few decades for it to replace Sn foil).

@sciencenotscary
Tin has two allotropes, a metallic one and a powder. It converts to the powder at Russian-winter temperatures. Napoleon’s troops had tin buttons on their jackets, which then wouldn’t close, and they died of exposure. Russia is the home of Dubna. Dubnium.

@ndbrning
One of the originally proposed names for Dubnium was Nielsbohrium, after Danish nuclear physicist Niels Bohr. Though this proposal wasn’t accepted, Bohr did eventually get an element named after him: element 107, bohrium.

@sumants
One of the two groups to have claimed discovery of bohrium in 1976 was led by Soviet scientist Yuri Oganessian, in whose honour we now have… Oganesson.

@robcarrphoto
Only 5 to 6 atoms of Oganesson have ever been detected. Originally thought to be a gas, computational chemistry revealed it would be a solid due to relativistic effects. Special & General Relativity were discovered by Albert Einstein, for whom Einsteinium was named.

@Stare_at_Air
Einstein (Einsteinium) famously developed his theory of relativity while working at the patent office. The first element to be patented was Americium.

@Mark_Lorch
Americium is created by bombarding uranium or plutonium with neutrons. It was first made by Seaborg (from Berkeley) in 1944 as part of the Manhattan project. Soooo many ways to go from here, but I’m going with… Seaborgium.

@Stare_at_Air
Shortly after the ACS announced 106 to be Sg (Seaborgium) in 1994, @IUPAC resolved not to allow names based on living people. Until it gave way about a year later, the IUPAC name for 106 was rutherfordium. In 1997, this name was instead assigned to element 104… Rutherfordium.

@chronicleflask
Rutherfordium was named after Ernest Rutherford, prob. most famous for the Rutherford atomic model developed after Geiger & Marsden’s gold foil expt. But he also carried out research into nuclear reaction bet. nitrogen & alpha particles.

@sciencenotscary
Nitrogen is usually thought of as being mostly inert an unreactive, until you make it an azide. Sodium azide is what inflates your car’s airbag in time to stop your head smacking the steering wheel.

@Mark_Lorch
After my grandpa died I helped clear his flat, over the years he had stashed various chemicals including 1/2kg of Na (sodium), KCN & conc HCl. To this day I shudder to think what might have been if I hadn’t been there to stop my family chucking it all down the sink. Chlorine.
(Side note: read more about that story here http://www.chemistry-blog.com/2013/04/18/chemical-nostalgia-my-grandfathers-lethal-legacy/)

@robcarrphoto
In organic chemistry lab, we used a lot of HCl (chlorine) of organic reactions, making salts, etc. But when I think of the Chemistry building, I think of bromine. The building smelled like bromine. The set of Beilstein books smelled like bromine.

@Mark_Lorch
Two of the elements stink. Bromine means “stench” and osmium means “smells”.

@ndbrning
Osmium is used in an alloy to make the tips of fountain pens hard and wear-resistant. In the past, iridium was used for this purpose, and sometimes the tipping material is still referred to as ‘iridium’ despite the element’s absence.

@Stare_at_Air
Not only was iridium discovered in the residue from trying to dissolve (impure) platinum, but Pt-Ir alloys are very useful, being both hard and chemically stable. The prototype kilogram is made of Pt-Ir, though a new definition of the kg comes in in May.

@sumants
The Pt-Ir (platinum) alloy was also used to make the prototype meter bar, which was replaced by a measure based on an electron transition within a Kr-86 atom. Krypton.

@sumants
While we’re going on about defining lengths, the Kr-86 (krypton) standard also redefined the ångström as 0.1nm, making obsolete the previous reference based on the spectral line of… cadmium.

@ndbrning
Cadmium is used in nickel-cadmium (Ni-Cd) rechargeable AA batteries. Due to cadmium’s toxicity, their sale has been banned in the EU for most purposes since 2006. They’ve been supplanted by another type of nickel-based battery, nickel metal hydride (NiMH).

@drdelusional
Breithauptite or NiSb (nickel) is a pale copper red colored mineral named after Johann Friedrich August Breithaupt, a Saxon Mineralogist. Antimony.

@chronicleflask
Antimony compounds have been powdered for use in medicine and cosmetics for thousands of years, often known by the Arabic name, kohl. Titanium dioxide is another common additive in makeup and sunscreens.

@Mark_Lorch
Titanium causes no immune response, making it an ideal material for implants. However it does slowly corrode in the body. A ceramic made of zirconia (zirconium dioxide) doesn’t suffer from this problem and is now commonly used for dental implants. Zirconium.

@drdelusional
Zirconium alloys are mainly used in nuclear reactors, however these alloys should not contain Hafnium.
(Side note: see this article for more info as to why http://www.iloencyclopaedia.org/part-ix-21851/metals-chemical-properties-and-toxicity/63/zirconium-and-hafnium)

@Stare_at_Air
Hafnium is one of two elements whose name is based on the Latin form of a Scandinavian capital — Hafnia is Copenhagen, while Holmia is Stockholm. Holmium.

@sumants
While working with erbia (grounds for a whole fascinating fork!), Per Cleve isolated two oxides, one which he called holmia (holmium oxide), and the other, thulia, which was identified as thulium oxide. Thulium.

@sumants
Thulium is commonly found in a mineral known as gadolinite, which is named after Johan Gadolin. While it doesn’t have much gadolinium in it, Gadolin wrongly thought a white metal he found in it was aluminium, and not… Beryllium.

@ndbrning
Beryllium is found in the mineral beryl, which emerald and aquamarine are precious forms of. One of the rarest varieties, red beryl, gets its colour from the presence of small amounts of manganese.

@chronicleflask
Manganese is used in REDOX titrations; the colour change from VII (dark purple) to II (pale pink) is very obvious. It’s commonly used to determine the amount of iron present. Another species that turns up in REDOX titrations is iodine/iodide.

@sciencenotscary
Iodine can occur in the form HIO₄, periodic acid, which looks like the word for the table we’re talking about but is actually per-iodic. A metallic compound with a very similar electronic structure is perhenate, based on rhenium.

@ndbrning
Rhenium was (possibly) first discovered by Masataka Ogawa in 1908, though he thought he’d discovered element 43, technetium (which wasn’t actually discovered until 1937).

@sciencenotscary
One of only two cis-uranic elements with no stable isotopes, it (technetium) had to be synthesised to be discovered (hence the name). The other one is protactinium.

@ndbrning
The first long-lived isotope of protactinium was discovered by Otto Hahn and Lise Meitner in 1917. 80 years later, in 1997, Meitner became one of only 16 scientists to have an element named after them… Meitnerium.

@MrVanOosterhout
Meitnerium was first produced by German nuclear researchers in 1982, who bombarded a bismuth sample with iron ions. A week of bombardment produced a single meitnerium ion, which lasted all of five milliseconds before decaying.

@chronicleflask
The name bismuth dates from around the 1660s, and it’s unclear where it came from, but maybe from Old High German hwiz (“white”). Like water, liquid bismuth is denser than solid, a characteristic it also shares with the element germanium.

@Stare_at_Air
The name germanium proved controversial, sounding like geranium. Jokingly, angularium was proposed, hiding a translated form of the discoverer’s name (Winkler). Lecoq denied doing something similar when naming gallium (Gaul, but also gallus = rooster).

@drdelusional
Gallium is a low melting solid (melting point ~30°C) and it combines with selenium to form Gallium Selenide which finds applications in nonlinear optics.

@sumants
Selenium was identified by Berzelius and Gahn from pyrite found in the Falun mine in Sweden, which is one of the world’s largest repositories of Copper.

@Mark_Lorch
Eight elements were first isolated from rocks quarried in a the small village of Ytterby in Sweden (same country as copper mine). Four of those elements are named in tribute to the village (ytterbium, erbium, terbium, yttrium)… Ytterbium.

@Stare_at_Air
Near the Ytterby (ytterbium) mine is this sign, discussing Gadolin’s work and the elements found there. It talks about a “tung, svart sprängsten” (in this case the black, heavy gadolinite), but it just reminded me of the origin of the name tungsten!

@drdelusional
A compound of Tungsten, Potassium tungsten oxide, is used in solar energy and water treatment applications… Potassium.

@DrMLHarris
Potassium comes in both fermionic and bosonic isotopes, making it ideal for the study of both Bose-Einstein condensation and cold Fermi gases. Lithium also has this property.

@DrMLHarris
The first molecular Bose-Einstein condensate was created in 2003 by pairing up atoms of fermionic lithium-6 (lithium) to make bosonic Li₂ molecules. Fermions are, of course, named after the physicist Enrico Fermi, who also has an element named after him... Fermium.

@sumants
Fermium was discovered in the fallout from a nuclear test, as was einsteinium when some filter papers were exposed to the same fallout. The work happened at the University of California, Berkeley, after which place we have… Berkelium.

@sumants
Berkelium is now synthesized mainly in the Oak Ridge National Laboratory in Tennessee, after which state, we have Element 117… Tennessine.

@DrMLHarris
Tennessine itself was synthesized at the Joint Institute for Nuclear Research in Dubna, Russia. The many contributions of this institute to the Periodic Table were recognized in the name of Element 115… Moscovium.

@sumants
Moscovium naturally underwent alpha emission and created… Nihonium.

DrMLHarris
Nihonium was named after the country where it was discovered, Japan. The discoverers expressed hope that this honour would help the country’s trust in science recover after the meltdown of the reactor at Fukushima, which uses uranium as fuel.

@sumants
Uranium, of course, is named after the planet Uranus. It probably makes sense, then, that its neighbour would be named after the planet’s neighbour, Neptune… Neptunium.

@Stare_at_Air
Despite many previous false claims of having produced element 93, including by Fermi, neptunium was first produced by McMillan and Abelson, at Berkeley Lab (yes, Berkeley again, of course), based in the state of California… Californium.

@sumants
Californium was first synthesized at the Lawrence Berkeley NL, which is named after Ernest Lawrence, after whom we have… Lawrencium.

@Mark_Lorch
Lawrencium is the final member of the actinides. Although it is arguably a member of group 3 along with scandium, yttrium, and lutetium… Scandium.

@sumants
When Mendeleev placed scandium in his periodic table, he had previously predicted its existence, which Per Cleve eventually confirmed. He named it eka-boron, since it would have been similar in its properties to… Boron.

@sumants
Borosil is a brand name that makes borosilicate glass, which is made from a compound oxide of boron and… Silicon.

@DrMLHarris
The A₃B group of compounds (A=transition metal, B=anything) wasn’t considered particularly interesting until vanadium silicide, V₃Si, (silicon) was found to act as a superconductor at 17K – one of the first Type II superconductors to be discovered… Vanadium.

@chronicleflask
Vanadium is famous for its many colours and oxidation states. The ability to readily change oxidation state makes it a good catalyst, notably for the contact process, used to make sulfuric acid. Another element which is used in catalysis is rhodium.

@ndbrning
Rhodium is used in catalytic converters in cars to remove nitrogen oxides, carbon monoxide, and unburnt hydrocarbons. Other metals used as catalysts in these converters are platinum and palladium.

@DrMLHarris
In 1989 Pons & Fleischmann claimed to have observed cold fusion via electrolysis of heavy water on a palladium electrode. That was false, but controlled hot fusion in tokamaks is real. Tokamaks use superconducting wire made from an alloy of tin and… Niobium.

@sumants
Niobium is named after Niobe from Greek mythology, and unsurprisingly, the next element one period down is named for her father, Tantalus… Tantalum.

@Mark_Lorch
Tantalum is one of those elements that was discovered in the rocks of Ytterby. Which gives its name to 4 elements, including … erbium.

@sumants
Along with ytterbium and erbium, the same rocks near Ytterby also yielded… terbium.

@DrMLHarris
Today’s main source of Terbium, however, is a mineral called bastnasite, which is named after yet another Swedish mine, Bastnas. This mineral is also a major source of… Cerium.

@Stare_at_Air
Cerium is named after Ceres, a dwarf planet hypothesised to contain an ocean of liquid water. A similar ocean is thought to exist inside Europa, the Jovian moon, named after the figure in Greek mythology. Also named after it is Europe… Europium.

@sumants
Europium(III) oxide is used to activate yttrium phosphors, mostly to create red on television and computer screens. Yttrium is also one of the elements to come out of the Ytterby mine.

@sciencenotscary
Like Yttrium, Indium is also used in screens because of its importance as a component of the semiconductor indium tin oxide.

@ndbrning
Radioactive indium ions have been investigated by researchers for their potential use in radiopharmaceuticals for diagnosis and treatment of tumours. Radioactive actinium ions have been investigated for the same purpose.

@mrfarabaugh
Actinium assumes oxidation state +3 in nearly all its chemical compounds. The Ac(III) ion has an electron configuration that is isoelectronic with Radon.

@sciencenotscary
Radon, being inherently radioactive, is a nuisance background for sensitive particle detectors. Another nuisance is thorium.

@Stare_at_Air
Thorium is named after Thor, the Norse god of thunder, on whom characters in many a comic have been based over the years. Prometheus, a Titan from Greek mythology, has also made an appearance in several comics and gives his name to element 61… Promethium.

@Mark_Lorch
Henry Moseley showed that atomic numbers corresponded to a physical property of the elements. Using this he found that some atomic numbers had no known elements: the gaps were 43, 61 (promethium), 72, 75, 85 (astatine), and 87.

@Stare_at_Air
All the group 17 elements up to and including astatine (“unstable”) are named after their properties (Ts ruined it), but many elements in the rest of the table are too. We still have two of these left — one of them is “hard to get” (though stable)… Dysprosium.

@Mark_Lorch
(Dysprosium) And the other is Barium which is derived from mineral baryte in which it is found. This in turn comes from the Greek βαρύς (barys) meaning heavy.

@DrMLHarris
Even heavier than barium, and much harder to obtain due to its half-life of just 22 minutes, the next element has never been observed in bulk, though like the other alkalis it has been laser cooled and trapped. Step up… Francium.

@Mark_Lorch
Marguerite Catherine Perey (a student of Marie Curie) discovered Francium and named if after her home country. France gets another hat tip in the table in the form of Lutecium which is named from the latin for Paris.

@DrMLHarris
(Lutecium) Another Paris-based discoverer was Paul-Émile Lecoq de Boisbaudran. He discovered three elements. Two of them, gallium and dysprosium, have been done already, but the third was… Samarium.

@DrMLHarris
De Boisbaudran is credited as Samarium‘s discoverer, but a different French chemist, Eugène-Anatole Demarçay, actually isolated the pure metal. Demarçay destroyed his eyesight in a chemical explosion. The godfather of explosive chemistry is Alfred Nobel… Nobelium.

@Stare_at_Air
Nobel (Nobelium) may have set up the Nobel prize because he was worried about being remembered for his contribution to developing more effective weapons. Georgy Flyorov also played a role in weapons research, as he encouraged Stalin to start an atomic bomb project… Flerovium.

@DrMLHarris
(Flerovium) The most dangerous isotope in nuclear fallout, the hazards of which helped to persuade the US, UK and Soviet Union to ban above-ground weapons tests, is strontium-90, which is taken up in the bones… Strontium.

@sumants
One of the popular electrode materials in solid oxide fuel cells is LSM, which is a perovskite (ABO₃) in which B positions have Mn, and A slots are occupied by strontium and… Lanthanum.

@DrMLHarris
The name “lanthanum” derives from the Ancient Greek for “to lie hidden.” X-rays are also good at revealing hidden things, from broken bones to chemical structures to black holes. They were discovered by Wilhelm Roentgen, who is honoured with Element 111… Roentgenium.

@sumants
Roentgenium was first created at the Helmholtz Centre for Heavy Ion Research in Darmstadt, from which we have… Darmstadtium.

@sumants
Several elements have been synthesized/discovered at the Helmholtz Center, including meitnerium, roentgenium, darmstadtium, bohrium, and… Hassium.

@sumants
(Hassium) I left out one more element synthesized at the Helmholtz Center: Copernicium.

@sumants
(Copernicium) The Helmholtz Center also helped confirm Element 116, which had been created partly in Dubna, and partly at the Lawrence Livermore NL, after which it was named: Livermorium.

@DrMLHarris
(Livermorium) All of these reactors used to discover ultra-heavy elements require good shielding against radioactivity. Because of its high neutron cross section, one of the elements used in shielding is… Gadolinium.

@Mark_Lorch
YEH!!! That was great fun! Thanks for playing! I honestly wondered if that was even doable!
#ElementTales

Periodic Table by Andy Brunning of Compound Interest (click for more)

Special thanks to Andrea Chlebikova (@Stare_at_Air) for keeping track of which elements had and hadn’t been covered as we went along.

You can also read an article about this project, published in Physics World, by Margaret Harris (@DrMLHarris).

Further thanks to: Mark Lorch, Andrea Chlebikova, Andy Brunning, Steve Maguire, Michael Farabaugh, Margaret Harris and Sumant Srivathsan. Follow the Twitter handle links to find these lovely people and give them a follow.