Tom Greenslade

"A Physicist Looks at Early Photography." Abstract: I came to Kenyon College in 1964 and soon learned that I was the successor to Prof. Hamilton Smith, who invented the Tintype
photographic process in 1856. Following in the footsteps of Charles Wheatstone and Oliver Wendell Holmes, I started to make black and white stereoscopic cards. And then I was given a
collection of Daguerreotypes and had to find out why a mirrored surface could duplicate nature. This talk tells about my adventures with nineteenth century photography.

"Let There Be Light." Abstract: On the end wall of my Apparatus Museum in Gambier is a 1939 "Map of Physics" by Cenco. The corner devoted to optics is pretty bare, and my aim in this talk is to fill it in with fascinating images and ideas that I have discovered in my own trips through the Land of Physics. Be prepared to see the biggest back-yard telescope in the world, early Egyptian photography, a huge magnifier filled with fish, a tooth camera, a method for putting ghosts into your plays, reflections in my 1890 wedding ring, and the technique of photographing yourself again and again and again...

"The Adventure of the Reluctant Collector." Abstract: “The apparatus collection of a physics
department can be modeled by a long, smooth shelf, completely filled with apparatus. When a
new piece is added, the entire collection is shoved down the shelf, and the oldest piece falls into ...? Very often it is the dumpster, but for over 725 items the Greenslade Old Apparatus Removals Company has been there to rescue it. I will talk about the museum wing that we added onto our 1850s house several years ago, and about some of the delightful pieces of apparatus from the 1850-1950 era that now live there.

"Physics and Art." Abstract: Do you know how the Irish plan to revive their economy? How do you build a cathedral without those annoying buttresses? What is the best place to eavesdrop on your friends? How does a spider add color to its web? How do you put a spectre into a play? These, and many other questions, are answered in this talk.

"Sparks and Wiggles." Abstract: The physics student of the nineteenth century learned physics though wonderful lecture demonstrations. Here are examples drawn from the fields of electrostatics and oscillations and waves, all illustrated with images drawn from my collection.
There is some physics, some history and some art in the study of sparks and wiggles.

"Learning Physics Lessons from the 19th Century." Abstract: The first part of the talk deals with various aspects of the 19th century physics course: the colleges, the faculty, the students, the books and the curriculum. As examples of how one might approach the large amount of available material, the talk concludes with a discussion of how much information you can learn from a picture (the 1844 frontispiece to a book on electricity) and how "modern" physics comes
from the intersection of two 19th century technologies: high voltage and high vacuum.

"Mechanix Illustrated." Abstract: This talk starts with the humble Inclined Plane, and it is all
downhill from there! First, there is a detour up Mt. Washington in New Hampshire and a trip in
a canal boat from the Shropshire Union Canal in England down to the nearby Severn River
before we investigate how a body can roll uphill. The tour then goes to the Isle of Man in the
Irish Sea where we will see Lady Isabella going round and round, and then to the province of
North Holland to see water traveling uphill, aided by the work of an ancient Greek. We continue
on to power dams in Washington State, observe water transport at the Isthmus of Panama and
see the Lockport Five on the Erie Canal. The talk ends with beats on sidewalks, roads and paper. The talk is lavishly illustrated with the modern form of Lantern Slides.

"Victorian Boys’ Books." The "rags to riches" books by Horatio Alger, the travel and war
stories by Oliver Optic (William T. Adams) and the adventure novels of the Englishman, George
A. Henty, formed much of my reading in my single-digit and early teen years. Over the years I
have made an almost complete collection of Henty first editions, which are fine examples of book design. Recently I have been rereading these tales critically to tease out some of the threads of character development during the second half of the nineteenth century. The Henty books give important clues to British attitudes toward the development of the British Empire.

"Early Electronics." Abstract: One day in my early teens my father sat me down and gave me the talk – about electronics! Under his guidance I was soon developing a technique for transmitting music on a light beam, building my first crystal sets, and beginning to understand how vacuum diodes and triodes worked. Later, after I took the electronics course in my junior year of college, I was introduced to more sophisticated vacuum tube electronics, which culminated in my senior honors project: a secondary frequency standard that weighed 100 pounds. Today you might wear this device on your wrist – if you are old-fashioned.

"Edwardian Boys’ Books, or Tom Swift and his Friends." Abstract: I inherited a large number of early twentieth century boys’ books from my father, and have added largely to the collection on my own. Some of the protagonists are familiar even today: Tom Swift (do you remember the “Tom Swifties” fad of the 1960’s?), and certainly the Rover Boys. You will meet the prototypical Boy Scout, Tom Slade, as well as the “Young Crusaders” of Akron, who are precursors of the BSA. The Moving Picture Boys will appear briefly, as well as a number of stalwart athletic heroes who just manage to win the last football game of the season. Boys in the early twentieth century liked to build things, and we will see books on how to work with metal and wood, and how to build electrical devices. And, we will meet the four wonderful volumes of “The Boy Mechanic” and see the Double-Elliptic Harmonograph that Tom Greenslade built from plans on its pages.

"The Shapes of Physics." Abstract: Physics is the field that allows us to connect mathematical
forms with the phenomena of nature. Here we see how the conic sections (hyperbola, parabola, ellipse and the circle), plus the helix, the cycloid, the catenary and the sinusoidal functions can be seen both in natural settings and in the laboratory. And, various types of harmonographs, devices that draw intricate shapes, will be shown, along with typical drawings made by them.

“Adventures with Oscillations and Waves.” Abstract: This is quite a different from the usual research seminar, for I shall tell you stories. The stories have a certain autobiographical slant, as I have long been interested in things that oscillate and waves that travel along. In my first year of college, the study of Simple Harmonic Motion helped me keep going in physics, where I had a long-term dream of becoming a professor of physics in a small liberal arts college. When that dream came true, I found apparatus in the back room that started me on a career of demonstrating waves. These dated from the 19th century, and they also started me on a parallel career as an historian of early physics teaching apparatus.