Cotsen Ghosties

book cover 3Last Halloween season we took a stroll through our special collections pumpkin patch. Today, we’re looking for ghosts! And we found them in this amazing optical illusion book titled Spectropia; or, Surprising Spectral Illusions. Showing ghosts everywhere, and of any color. Published by J.H. Brown in London in 1864, the book teaches the concept of “the persistency of impressions, and the production of complementary colours on, the retina.”

The illusion is very simple. In the image above, stare at the small black dot by the ghost’s neck for 20-30 seconds. Then look away at a white wall or ceiling. Her ghostly image will appear in your vision, except in different colors (in this case green wreath, blue ghost)!

Scientifically speaking, this is called an afterimage. The color receptors in your eyes work in pairs (red/green, blue/yellow, etc.). When you stare at the drawing and one color fatigues your receptors, the other receptor will step in and dominate for a bit.

The book has a very lengthy description of this concept, as well as viewing instructions that include having the “gaslight turned low.”

Spectropia also has a disclaimer at the beginning: “As an apology for the apparent disregard of taste and fine art in the plates, such figures are selected as best serve the purpose for which they are intended.”

I wish they might have reprinted the disclaimer before THIS image, which honestly is going to haunt me clear through December:

The book concludes with a grand finale image that is not a ghost, but a rainbow! Definitely try this one, because it is so cool to see the colors flip in the afterimage!

Looking more more optical spooky fun? Try making our tabletop Pepper’s Ghost illusion!


Images from Spectropia; or, Surprising Spectral Illusions. Showing ghosts everywhere, and of any color. J.H. Brown, London. Griffith and Farran.1864. Cotsen Children’s Library, Department of Special Collections, Princeton University Library.

A Library for the Birds

A heads up for our readers…in addition to eggs and nests, this post contains multiple images of bird taxidermy, which some may find unsettling. If you do, no problem! Skip this particular post, and we’ll see you on the blog next Tuesday!

Deep within Princeton University’s Department of Ecology and Evolutionary Biology, there is a plain door with a fairly innocuous sign mounted nearby:

Behind that plain door, however, is an amazing treasure trove of natural history. It’s the Princeton Bird Collection, which contains a taxidermy catalog of over 6,000 bird specimens, some of which are over 150 years old! Many were collected by William Earl Dodge Scott, who was appointed Curator of the Department of Ornithology in 1879.

Princeton’s bird room contains a multitude of hulking gray metal cabinets. While I’m used to our library’s special collections cataloged and ordered on regular bookshelves, the bird room’s cabinets open to reveal horizontal wooden drawers containing various specimens. These collections are available for teaching and research, including the Stoddard Lab’s research on avian coloration and morphology.

The drawers also contain nests and eggs, which are similarly laid out for researchers:

There are larger nests as well, including this amazing one that I’m pretty much ready to curl up and take a nap inside:

Beyond the drawers are a fantastic assortment of standing taxidermy, both large and small. Below are just a few the staff unwrapped for me to photograph…from top left to bottom…an emu, ground hornbill, kiwi, barn owl, macaw, snowy owl, and golden eagle.

And check out this! It’s a quetzal, which hails from Central America. It was was considered sacred by the Ancient Mayas and Aztecs. The photo really doesn’t do it justice. The coloring on the bird is simply exquisite.

The bird collection also contains the documents and journals of Charles Roger, a professor of ornithology at Princeton from 1920-1977. The journals, which he began as an eager boy of eleven and continued until he was eighty-four are a fascinating and informative body of work. You can read more about the digitization of his works, and find some awesome coloring pages from our special collections here (as well as a couple fun bird projects!).


A very special thank you to Cassie Stoddard, Assistant Professor in Ecology and Evolutionary Biology, for arranging for me to photograph the bird room, and answering my questions about ducks!

Lifestyles of the Rich & Noble

Don’t be sooooo 12th century. Get with the times whilst also enjoying this complementary copy of Medieval Vogue! Katie designed this gorgeous little mag for a massive Robin Hood shindig my library hosted some years ago. If you’d like to browse Medieval Vogue for the newest trends in poulaines this season, here is part 1 and part 2 *. For more about the event, read on!

Robin Hood was the book du jour for Princyclopedia, an annual large-scale event that involved bringing a book to life from all sorts of angles – history, science, music, art, food, performances, live animals, you name it! Each table had either a demo, a hands-on activity, or something cool to take home. The 2-sided event map showed you all the table activities and also matched relevant book quotes or historical blurbs to them.

Medieval Vogue was a free take-home at the “Lifestyles of the Rich & Noble” table. Here, we were delighted to be joined by Rose Fox and Kim Hanley from Medieval Scenarios and Recreation.They brought TONS of clothes and costumes for kids to look at and try on, and answered questions about fashion from this time period.

At another table, we had a different take on wearables. Namely, the armor of Sir John Williams (right) and friend (left), two knights who professionally joust at Renaissance Fairs! They brought all their gear and expertise and were simply amazing.

We had a TON of other activities as well…the chemistry of alchemy, venison chili, musical performances on period instruments, live hawks, the science of stained glass, actual longbows with a kid-safe shooting range, illuminated art, the math of taxation, a big play space with multiple cardboard castles, the science of stained glass, herbal amulets, siege engines, gargoyle sculpting, nature tracking, professional stage fight demos, forest conservation, two free roving court jesters, and more! And yes…a table on all the Medieval jobs you DON’T want.

Another fantastic component of the event is that it was a food drive. Families were invited to bring can and box goods to the event to benefit the Arm in Arm food pantry (formally the Crisis Ministry of Mercer County). We donated almost 500lbs of food!

I’ll finish today’s post by sharing the literacy-based table the Princeton Public Library hosted. Since literacy was uncommon during the Middle Ages, shops typically featured pictures of their goods and/or services on their signs. So we designed a game! First, we selected a bunch of images of Medieval signs. Then, we asked kids to guess what the signs represented. Rothenburg, Germany has some fantastic signs currently in use (it being an actual historic Medieval town, wow!).

Image source Wikipedia

We also wanted kids to make a personal connection, so Katie and I photographed a few local shops. We photoshopped out any words, then asked kids to guess what the signs represented. They were tickled to recognize signs they saw everyday and make a Medieval literacy connection!


* Images used for Medieval Vogue may be subject to copyright. Please contact danas@princeton.edu if you are the author of one or more of images used here and have objection in such a use.