Author: chemphasis

The images: nightfall, abstracting, / 
With chemistry vivid-impacting. / 
A mid-July verse /
Heralds ROY-G-BIV bursts, / 
As fireworks’ light is diffracting.  

This next summer poem centers around some photographs I took at my town’s Fourth of July celebration a few days ago, using a diffraction grating over the camera lens.  Given my low-key and time-sensitive “experimental question” that evening (essentially: will this work?), I was pleased to see how these turned out.     

“The images: nightfall, abstracting, / 
With chemistry vivid-impacting.”

I was inspired to try this after seeing some June updates from the superb Science History Institute in Philadelphia; they had posted some social-media images of their exhibition of historical fireworks as viewed through diffraction gratings, yielding characteristic rainbows. 

I was intrigued as to whether I could see any similar effects with the more familiar aerial fireworks, given that those are farther away and fleeting in timescale, at the then-upcoming Independence Day celebrations in my own town. 

It was fun to quickly discover that it indeed did work!  

The tell-tale diffraction effects were immediately visible, and the resulting photos preserved them.

“A mid-July verse /
Heralds ROY-G-BIV bursts, /
As fireworks’ light is diffracting.”

Diffraction occurs when light passes through a small opening and its waves spread out.  A diffraction grating is made up of regular, tiny openings that yield a consistent pattern. White light consists of the entire ROYGBIV rainbow of visible light, and so when it passes through these openings, the different component colors are spread out to different extents.  This phenomenon is most pronounced with the longest-wavelength light; for instance, we can see how red is “farthest” from the central firework in the photos above, since red light has the longest wavelength of visible light.       

My July 4 investigation took about as simple an approach as it possibly could; it was a linear diffraction grating (so splitting light into ROYGBIV colors along one axis only), and I taped it over my phone camera.  

I could imagine many next steps, if I had not been in a crowd where viewing space and time were both at a premium.  I later wished I had tried at least rotating the filter to see the horizontal diffraction, and I had originally contemplated taking a few more complex gratings along, to yield images in both directions at once (but the cost-benefit analysis in terms of annoyance to my neighbors did not seem worth it, especially in a first attempt!).  I was also intrigued as to how/whether different colors of fireworks yielded obviously different observations, although I would guess that virtually any of them generated enough white light to see some ROYGBIV splitting, as with the red firework below.  

On a related note, the chemistry of fireworks themselves (their molecular-level chemistry, not just the behavior of the resulting light) has been explored and documented in many excellent sources. For instance, the website Compound Interest has a beautiful infographic that describes the multiple chemical components and their roles.  The Smithsonian’s science education blog likewise presents a fascinating historical and scientific overview.  

*** 

I will close this week’s essay with my favorite photo from that evening.  The diffraction and the non-symmetric setup of the shot combined to give rise to a more artistic effect.

A saga explaining a candle /
(Complexity disarmed/dismantled / 
In trial-and-error ways /
From one Michael Faraday) / 
Sheds light on themes too hot to handle.  

This week’s post summarizes a fascinating record from the history of science that, as with many themes I examine here, I was fully unaware of before beginning these essays.  It will take a brief look at “The Chemical History of a Candle,” a set of lectures and demonstrations from chemist and physicist Michael Faraday (1791-1867).  

“A saga explaining a candle…”

London’s Royal Institution hosts a long-standing tradition entitled the Christmas Lectures, in which a renowned scientist presents on a subject of particular interest to students during the December holiday season.  In 1848, the theme was “The Chemical History of a Candle.” 

“(Complexity disarmed/dismantled /
In trial-and-error ways /
From one Michael Faraday)”        

Via the familiar example of a candle, scientist Michael Faraday introduced an astoundingly wide range of complex topics in his 1848 lecture, as can still be read in the record of his lectures at Project Gutenberg.  He states in the introduction: “There is no better, there is no more open door by which you can enter into the study of natural philosophy, than by considering the physical phenomena of a candle.”    

Via experiments and demonstrations (in the moment), along with the written explanations recorded for posterity, Faraday discusses complex themes including the molecular composition of the candle and mechanisms of combustion.  His communication style is clearly geared towards students; he “disarms [and] dismantles” complex jargon by working through questions methodically, addressing his audience directly, and encouraging the students to follow his thought process.  (In many ways, Faraday’s theme addresses Alan Alda’s famous Flame Challenge, nearly two centuries before it was posed!)  Additionally, the lectures were accompanied by the “trial-and-error” of thorough demonstrations.    

These lectures were an inspiring find.  I had encountered Faraday primarily with respect to his disciplinary insights into physics and chemistry throughout my schooling, given his research related to electricity and magnetism.  It was fascinating to read of his interest in science communication and public service, as well.        

“Sheds light on themes too hot to handle.”      

The last line primarily connects back to two common idioms related to the behavior of a candle, related to its light and heat, and acknowledges that these lectures would have played a major role in demystifying a complex set of topics. 

***

I will also note here that the idea of a broader, more historical look at a candle also highlights a further connection back to Jonathan Swift‘s famous allusion to “sweetness and light” (by way of his 1704 “Battle of the Books“). He invokes there a fable involving the honeybee and the spider. The bee is responsible for two larger phenomena of sweetness and light, respectively, via honey and beeswax; the beeswax in particular is commemorated via its crucial role in candle formation and thus the production of light.

I spent much of my time in graduate school examining highly technical, jargon-heavy views on combustion, so I am always fascinated to find much more lyrical discussions of similar themes in literature and history. This tangent will likely be worth a future essay of its own, but I’ll just acknowledge for now that I am most aware of these larger themes via their discussion in Stephen Jay Gould’s The Hedgehog, the Fox, and the Magister’s Pox, which I summarized in a post last summer.

The focal length: conceit insightful /
In effort to find lensing rightful. /  
Close-up, panoramic, /
Or scope more dynamic, /
For stories hued deep to delightful.  

This week’s poem makes yet another summer jump, this time back to the concept of “focal length” as a metaphor for artistic viewpoint.  This builds from an insightful metaphor in Twyla Tharp’s The Creative Habit and is an image I’ve found helpful before.  

“The focal length: conceit insightful /
In effort to find lensing rightful…”

I was reminded of “focal length” this summer in hearing an outstanding podcast related to a (likewise outstanding) book by Victoria Finlay, as both overlapped with a topic I’ve taught in class.

The concept of the focal length, as introduced in Tharp’s book, pointed out that artists often engage with their work via one of three perspectives.  She writes, “All of us find comfort in seeing the world either from a great distance, at arm’s length, or in close-up… [W]e focus best at some specific spot along the spectrum.”  

I’ve discussed here before how, as I’ve been writing more creatively about chemistry topics, I’ve realized that my teaching relies fundamentally on the “arm’s length” view afforded by discipline-specific jargon.  It’s been humbling to realize how much I have to learn about the other two views, in communicating via more accessible writing about either molecular behaviors (“close-up”) or big-picture phenomena resulting from those behaviors (“great distance”). Finding the “lensing rightful” is an ongoing challenge.

“Close-up, panoramic, /
Or scope more dynamic…”

I have found some interesting support and connections this summer in considering this challenge.

I encountered the National Gallery’s superb podcast “Stories in Colour” last year and have greatly enjoyed it since.  This season, they presented an episode on ultramarine blue, as the natural pigment that is responsible for blue in older paintings. 

In terms of “focal length,” the jumps between various perspectives were fascinating, as the discussion moved from the mineral underlying the pigment (“close-up”) to the pigment’s use (“scope more dynamic”) and ultimately to several applications across art history (“panoramic”).  Victoria Finlay was a guest expert commentator, and I realized in listening that I’d read her excellent book on pigments years before.  I was particularly taken by how one of her most striking images was used in both her podcast interview and her book, but in different places.  

A brief bit of background: historically, ultramarine blue was a much rarer pigment than those used for other paint colors.  The mineral lapis lazuli was the expensive source for the color, due to its challenging geography and preparation (themes I will likely revisit more succinctly via an April 2026 poem when I’m in “Chem in Art mode” in the autumn).  Famously, Michelangelo left his 1501 painting The Entombment unfinished, and scholars speculate that it is because he had been waiting on a delivery of ultramarine blue pigment from a patron, with which to depict Mary and her traditionally blue robe in the lower right corner.  It did not arrive in time; Michelangelo moved on to other projects; the gap itself is now a major aspect of the painting.    

This story is what Finlay uses to introduce her chapter on blue in her book Color: A Natural History of the Palette.  Listening to the podcast on blue, I noted that in the Q&A format, the discussion of Michelangelo’s painting did not arise until much closer to the end.  Both presentations worked incredibly well, and I found myself thinking about why.  In this case, it wasn’t so much that the focal length changed that the medium did. 

A podcast, with its interactive approach, can draw in listeners in a different way than a book chapter, which must asynchronously stand alone.  The story of the painting raises such an interesting question (I remember literally “minding the gap” in reading Finlay’s book, in that I quickly was invested enough to continue on and seek out the answer!) that it is a perfect lede with which to begin a written chapter.  The podcast began with more technical, close-up information, bolstered by the inherently insightful, accessible Q&A format; it could build to a later discussion of the painting.

“For stories hued deep to delightful.”

As I have been working on more general writing here and via other projects, both focal length and medium are helpful constraints to keep in mind, in sharing stories from chemistry more broadly.  (Many of these stories have begun in the interdisciplinary overlap of chemistry and art, for me, as highlighted by the telltale use of “hue.”)

Revisiting past brumal season / 
With temperatures far below freezing; /
Some close illustrations /
Of precipitation /
With metaphors pushed beyond reason.  

I often post “out of season” poems here with respect to the spring, since my routine of revisiting the NaPoWriMo routine often means that I am posting about the start of April in the start of fall semester.  This eclectic-summer post will consider a less common juxtaposition: revisiting Winter 2026, when the snowfall and the cold temperatures were more dramatic than in much of the past decade.

“Revisiting past brumal season / 
With temperatures far below freezing…” 

This is not a chem-themed limerick so likely does not need much in the way of translation!  One synonym for “wintry” is “brumal,” and this particular winter season had much consistently colder temperatures than the last several. 

“Some close illustrations / Of precipitation…”

The extreme weather yielded some particularly interesting photos of snow and ice, over January and February.          

“With metaphors pushed beyond reason.” 

I had drafted a different poem back after the worst January snowstorm, based entirely on rhymes for “winter” that were coming to mind (as I frustratedly excavated my car for the morning commute!):

“The nearby path, a wintered pass / As pond suggests near-sintered glass./ Car rests beneath snow’s splintered mass. / The morning’s goal: get into class.”  

This verse arose from rhymes first, and then I considered the actual context later.  The sintered-glass funnel cited above is a piece of equipment I know from labwork; the pond had certainly been glassy in its appearance, but “sintered” did not particularly apply.  Likewise, the “splintered mass” of snow and ice was relatively straightforward to deal with, given enough time and patience.  The metaphors were “pushed beyond reason” in commemorating the winter weather.  

O’er course of career here-amassing, /
From teaching and testing and “class-ing,” /
Note margins’ connections /
In varied directions: /
The value of comments in passing.  

The first of these more random summer essays discusses a point I’ve found intriguing throughout my career: often, the most directly insightful comments, in terms of actually doing day-to-day work, are not presented in the most typical educational arenas.  

(I expect that many of these summer essays will run long, compared to my typical 280-word limit, and I’ll just provide that overall acknowledgement here.)         

“O’er course of career here-amassing, /
From teaching and testing and ‘class-ing’…”

The traditional path toward a faculty career in STEM (graduate school and postdoctoral work) is primarily focused on depth, in terms of developing specific research expertise, rather than in the breadth that will be useful in teaching courses. As I examined last summer, that tension is a fascinating one that many more established authors have explored, in much more detail than a brief blog post would allow.  

Thinking of my own experience, it can be interesting to reflect on where the most pertinent on-the-job training has come from, for preparing and teaching classes.  I’ve certainly had formal instruction in my own career (campus centers for teaching and learning; the Preparing Future Faculty program; excellent books).  However, much useful advice also has arisen in side comments from my own professors, in settings like office hours, grading sessions, and conference travel: e.g., what can be specifically challenging about writing an exam, or why scientific curricula have the overall structures that they do.             

“Note margins’ connections /
In varied directions…”

When I was expanding this poem this week, I thought of two science essays I had encountered in the past. 

In “The Proof of Lavoisier’s Plates” (from the excellent compilation The Lying Stones of Marrakech), paleontologist Stephen Jay Gould begins by discussing the usefulness of notes in the margin, for “two most contradictory forms of intellectual activity.” For one, he acknowledges that the term “marginalia” is often used as a catch-all designation for seemingly minor points and tangents; for the other, he points out that a reader’s own notes in a book’s margin often mark the genesis of their own independent insights or thought processes related to that book.  A quick annotation can ultimately have a massive domino effect.   

In botanist Hope Jahren’s memoir Lab Girl, she movingly discusses an encounter that, again, defies obvious classification.  Here, a past mentor retires and donates his lab equipment to her: “[W]e two scientists conducted a homely ceremony that transferred the tools of his life– his career– to mine.”  She invokes an image that has stayed with me for a near-decade at this point: “It was kind of tragic, I reflected, that we all spent our lives working but never really got good at our work, or even finished it.  The purpose instead was for me to stand on the rock that he had thrown into the rushing river, bend and claw another rock from the bottom, and then cast it down a bit further and hope it would be a useful next step for some person with whom Providence might allow me to cross paths.”  

Both Gould’s and Jahren’s essays highlight additional opportunities for these informal moments of insight and support that arise throughout a more formal career.  Moreover, they remind me of a perpetual favorite image, of the poetic form of the rubaiyat: casting the poem’s rhyme scheme forward into its next stanza, projecting how the next likely steps will take shape.  Here, the marginal note and the equipment transfer could potentially provide a scientist with both a new question and the means with which to explore it.      

“The value of comments in passing.”

Academia certainly has occasion for many formal settings and events: classes, seminars, exams, defenses, and graduations, just to name a few.  However, the metaphorical margins and “comments in passing” likewise abound, in the course of a scientific career.  

Detouring past peak summer-dozing
Through June and July, months enclosing,
Find poems anew.
Topics random ensue:
A summer of theme-juxtaposing.

May has officially disappeared in its typical blend of semester-ending meetings and tasks. Most years, I tend to realize the summer is on the wane at the end of June, but I’m aiming to use the season a bit more productively this time around.

Detouring past peak summer-dozing /
Through June and July, months enclosing, /
Find poems anew.

The end of the academic year is hectic enough that I doubt I’ll ever manage to completely bypass “summer-dozing” entirely. May brings a welcome break from course prep and teaching, but it also starts a sequence of catching up on appointments. I usually am in recovery mode during any down time from the latter.

I’ve seen since beginning this website that it’s been quite rewarding to dedicate at least some time over the summer to non-academic writing. Topics have varied over my July efforts in the past few years: I have revisited some biographical and teaching themes, used specific lines from literature as inspiration for short essays, expanded on conference presentations from previous years, and revisited some overlaps of STEM and the humanities.

My goal for this summer is to get to that writing-focused stretch a bit sooner: in other words, to spend some time in both June and July on “poems anew” and the ideas they summarize.

Topics random ensue: /
A summer of theme-juxtaposing.

With all that said, I expect that it might be a bit more random of a collection of posts than in past summers, to cover all nine weeks in this portion of the year! I will be interested to see, when I revisit things at the close of this stretch, if the resulting “theme-juxtaposing” has led to some interesting parallels I am not directly anticipating at the moment.

“The month’s new-complete contribution /
Re: concepts, reactions, allusions; /
A break from spring’s stressing: /
Chem-terms, verse-addressing, /
In welcome routine’s resolution.”

The 30 April 2025 Bluesky limerick marked the end of my seventh attempt at the National Poetry Writing Month (NaPoWriMo) tradition, and this is our last week of spring classes, so it is a good day to formally end the 2025-2026 “academic year” posts.  

“The month’s new-complete contribution /
Re: concepts, reactions, allusions…”

April 2025 was the seventh NaPoWriMo routine I completed in terms of daily science-themed poems; my routine began in April 2019 with the overlap of National Poetry Writing Month and the International Year of the Periodic Table. 

Over the years, some of these poems have summed up specific chemical concepts; others address reaction mechanisms; several allude to figures from history or famous scientific stories.  

“A break from spring’s stressing: /
Chem-terms, verse-addressing, /
In welcome routine’s resolution.”

I am now a few weeks into my eighth version of this April tradition– or rather, I hope I will be, since I write and schedule these essays a few weeks ahead. If so, I suspect it will be the last one in terms of such formal adherence; it would be appropriate to end with a “full octet” of the April poem collections.  I’ve also noticed that I don’t need the cyclic routine quite as much in generating ideas for posts as I did in the first few years of the website.  

In an academic term, though, NaPoWriMo arrives at a particularly opportune time to merit “a break from spring’s stressing,” so time will tell.  For now, I’m glad to bring both the 2025 poems and the 2025-26 essays to a welcome resolution.

“To celebrate day metrologic / 
With global theme, STEM-philosophic, /
This May marks attention /
To Metre Convention /
As sesquicentennial topic!”  

I’ll go slightly out of order with revisiting this particular poem, so that I can wind down NaPoWriMo2025 as I formally end my Spring 2026 semester next week.  This poem was posted on Bluesky to celebrate World Metrology Day 2025.  

“To celebrate day metrologic / 
With global theme, STEM-philosophic…”  

World Metrology Day is celebrated on May 20 each year; it celebrates the date on which the International System of Units (the metric system) was adopted in 1875.  (The phrase “SI units” is often used as a shorthand, given the system’s name in the French language: “Système international d’unités.”)  This was a banner day in the history of science; it marked a shift toward standardized, universal communication, or a “global theme, STEM-philosophic.”

“This May marks attention /
To Metre Convention /
As sesquicentennial topic!” 

In 2025 specifically, the World Metrology Day celebrations were particularly festive, as it was the 150th anniversary (or the sesquicentennial) of the original Metre Convention in Paris.  

The metric system had been proposed by France in 1799.  The meter was first defined based on measurements of the Earth, and the kilogram was first defined based on a certain amount of water (these units represented far more egalitarian measurements than, for instance, a king’s foot).  In 1799, France defined the units in relation to specific prototypes that were then housed in the National Archives.  At 1875’s Metre Convention, several such standards were then distributed internationally.

The metric system has been adjusted in the years since.  In 2019, famously, the seven base SI units were redefined in terms of the fundamental constants of nature, so that their values no longer hinge on physical objects.     

(Metrology is a subject that tends to be highly condensed in a science course; we focus more on using and interconverting a few specific types of units than the history of measurement itself.  James Vincent’s outstanding 2022 book, Beyond Measure, recounts several fascinating stories.) 

“Acidic-environment feature: / 
Oft-stable reactant’s chem-cleaver. /
The process provides / 
Alcohol and halide: /
Two products formed out of the ether.”  

The 29 April 2025 Bluesky limerick addressed another common organic chemistry mechanism.  

“Acidic-environment feature: / 
Oft-stable reactant’s chem-cleaver…” 

I’ve addressed the idea of a “functional group” before in this space.  The term refers to a characteristic pattern (group) of atoms that shows up across a large number of molecules and governs, in part, how such molecules can react (function).  

One functional group is the ether: an oxygen atom singly bonded to two alkyl (hydrocarbon) groups, abbreviated as R-O-R’, where R and R’ generically represent the alkyl substituents.    An ether does not have the panoply of subsequent reactions available to it that many other functional groups do (comparatively, it’s an “oft-stable reactant”), but a few steps are feasible.

One pathway available is called acidic cleavage: the ether breaks apart in acidic conditions.    

“The process provides / 
Alcohol and halide…”

Lines three and four of the limerick are not comprehensive: the fate of an ether in acidic conditions would depend on whether the alkyl groups surrounding the oxygen are more amenable to substitution or elimination reactions.  

However, in one simple case, an ether (R-O-R’) could react with acid to form an alkyl halide (RX) and an alcohol (R’-OH): as shown here:
R-O-R’ + HX → RX + HO-R’ 

[This would be an essential reversal of what is probably the most famous reaction involving ethers: the Williamson ether synthesis, named for Alexander Williamson (1824-1904), who developed it in 1850. Here, an alcohol is deprotonated in basic conditions; the resulting alkoxide ion reacts with an alkyl halide to form an ether.] 

“Two products formed out of the ether.”

The idea for this poem began with the idiom “out of the ether.”  I was intrigued to see whether I could reach that phrase via a reasonable chemistry discussion, and this generally seemed to work.