microscope slides
#AdventBotany Day 10: Have yourself a microscopically Merry Christmas
At this time of year, there is always that one person who is impossible to buy a gift for. What do you get a botanist who has everything? Well, how about some microscope slides?
As we’ve been working our way through Manchester Museum’s 15,000 microscope slide collection, I can’t help but imagine some of these as presents. For starters, there’s all that beautiful paper; no gift is complete without the careful wrapping. Early microscope slides were wrapped in paper to keep the coverslip in place on top of the specimen. Other methods for attaching the coverslip were developed, but some slide preparators continued to use the papers for decoration.
Just imagine the fun your botanical friend could have looking at the finer details of the fruit and veg and sharing their findings over the Christmas dinner. While the word ‘fruit’ in English is used for many sweet-tasting plant parts, its use is much more specific in botany. There are a considerable number of ways by which any aspiring botanist can learn to describe their fruits and distinguish one kind from another. They might offer a slice of soft, juicy, pickled pepo (cucumber) with the cheese, warn fellow diners to take care with the hard stone in their delicious drupe (date), join in the struggle to break into a true nut (walnut) and, my personal favourite, uncover the zesty heperidium (tangerine) at the bottom of their Christmas stocking. Not forgetting, of course, there is always the chance to put people off their dessert by explaining the intricate way that the highly specialised fig flower structure is visited by wasps and develops into the culinary fruit (technically known as a synconium; I wonder if that would get a good score in Scrabble?) .
A set of slides could be an opportunity to escape another round of charades and escape to some quiet contemplation! Perhaps of the Christmas tree in extraordinary detail. Just imagine the pleasure getting lost for hours in the patterns created by slicing the timber in different directions, with or across the grain. Or maybe a close investigation of a local nativity scene – is that really hay in the manger? Or is it a much scratchier bed of straw?
The fortunate recipient of your microscopical gifts can follow in the footsteps of Mr George Wilks, who was clearly snipping bits off the decorations in 1903. Perhaps he needed to test out a new microscope from Santa.
Further reading
Fruit: https://awkwardbotany.com/2014/10/04/22-botanical-terms-for-fruits/ and
https://botanistinthekitchen.blog/2013/02/04/pomegranates-and-the-art-of-herbivore-attraction/
Microscope slides http://www.victorianmicroscopeslides.com/history.htm
Historic Manchester (2)
This is Abraham Flatters and his image is on a lantern slide which was used in a magic lantern as an early form of image projection. Abraham Flatters was an expert at making these and he went into business with Charles Garnett to form the successful company Flatters and Garnett.
They supplied both lantern slides and microscope slides on many aspects of Natural History to universities. Those which were bought by the science departments of the University of Manchester (then Owens College) are now in the Manchester Museum collections. We also have many of these very nice display boxes which demonstrate showing various features of british trees.
There is a very good history of this Manchester firm produced by the Museum of Science and Industry which can be read here. If you’re interested in the history of Manchester then there are more activities taking place in the city for the Manchester Histories Festival which comes to a close this weekend. Don’t miss the big Celebration Day at the Town Hall where we will be giving a selection of museum objects some time in the spotlight.
Microphotographs
Whilst cataloging some of the large collection of microscope slides in the herbarium I came across some slides with intriguing labels. One was labelled ‘The Moon”, another “Nelson Meditating His Prayer before the Battle of Trafalgar” and another “£20 Bank Note” – not the kind of thing we normally come across in the botany stores. I immediately set about viewing the slides under a microscope and was amazed to actually pictures of Nelson, the moon and a bank note. In the corner of the slides was the initial J.B.D.
After a few minutes on Google, I discovered that these slides were made by the 19th Century Manchester instrument maker and inventor of microphotography, John Benjamin Dancer. Dancer’s first example of microphotography was produced in 1839 and they soon became popular with microscopists.
“Dancer did not have any mass production method for turning out his micro-photograph slides and though it must have been very time consuming he is reported as having made many thousands. The method employed was explained by Mr.J.F.Stirling writing in Watsons Microscope Record No.45, Oct.1938, p.16. A glass negative of the photograph to be reduced was placed in a lantern illuminated by a flame. The image of the photograph was projected through a microscope objective mounted horizontally on to the sensitized collodion film supported on a glass sheet. Dancer speeded up production slightly by duplicating the contraption with two lanterns placed back to back with one illuminating flame in the space between the two lanterns, the whole assembly being covered over with a canvas tent to keep out the light. The exceedingly small piece of collodion film containing the positive microphotograph image was mounted in balsam beneath a cover glass on a standard 3 x 1 slide.” – The Microphotograph Slides Of John B. Dancer and Richard Suter by Roy Winsby
The practice of mounting microphotographs eventually became seen as frivolous by serious microsopists and their popularity waned. However, during the Franco-Prussian War the benefits for smuggling information on microphotographs meant that the technology developed by Dancer was given a new and very practical application.
Here is a list of Dancer’s Microphotographs.
Thanks to David Green for taking the photos of the slides.
Herbology Manchester 
