Showing posts with label hand lens. Show all posts
Showing posts with label hand lens. Show all posts

Friday, February 19, 2016

Professor Small's Book of Tiny Wonders


When I went to university to read for a degree in botany, almost 46 years ago, there were only three pieces of equipment that I had to take with me:


  • A white lab coat (bequeathed from my grandfather who was a dairyman and wore one for his daily work)
  • A dissecting kit with a cut-throat razor for cutting sections of plants
  • A hand lens, because a botany degree in those days involved a lot of field work


What reminded me of all this was this little book - Pocket-Lens Plant Lore by James Small, published in 1931, that I bought a few years ago for 50p. in a second-hand book shop. 

The author, appropriately named for someone who was writing about tiny objects, was Professor of Botany at Queen's University Belfast and seems to have written the book for his children, because the dedication reads:

To Sheila and Donn,
two small children who wanted to 
SEE THE INSIDES OF THINGS



































It's a charming little book that, month-by-month, uses a hand lens to explore the features of 192 different plant species, including their buds, leaves, flowers and seeds.



































There are pages of small illustrations for plants that are in season, showing details of their external features and internal structure that's visible in sections of stems.























This is a page for February, showing groundsel, white willow, oak, privet, elm, birch and laurel. For every species there is a page of description for the features you can expect to see with a hand lens.

















Methods were simple, needing just a hand lens, a pair of self-closing forceps and a razor blade ....


... all of which I had lying around, so I took the book for a test-drive using lungwort Pulmonaria officinalis, which was flowering in the garden today.



Here's Small's drawing of the features to look out for and....























... here is the accompanying page of description



































Sure enough, the two kinds of hairs on the flower stalk that he mentioned were there: stiff pointed ones on a pediment, that make the plant feel bristly, and shorter ones tipped with a gland that produces a slightly sticky secretion.





















And here are the hairs in the corolla tube that he talks about. It may be that they help to deter small nectar thieves like ants, because ....























... here is the flower with the corolla removed, as he advises. That square of yellowish tissue is made up of the nectaries. 

Inside, at the base of the stigma and style, the four 'eggs' are the ovaries containing the ovules that will eventually become four black seeds, in an arrangement that is typical of the Boraginaceae, the family to which lungwort belongs.

What I really like about this book is that it's aimed at satisfying the natural curiosity that all children are born with.

I'm planning to produce an updated photographic version for my own grandchildren. 

Friday, May 20, 2011

Germander Speedwell


When I started out as a student of botany  over 40 years ago there was one vital piece of equipment  that we were expected  to carry at all times – a hand lens. So when we found a plant, like the germander speedwell  Veronica chamaedrys in this  photograph - we could take a really close look at it even if it was an easy one to identify and we knew what it was....















......first scrutinising the floral characteristics, vital for identification, and then the rest of the plant, which often revealed...

........ unsuspected beauty. Germander speedwell has two straight lines of hairs running down opposite sides of the stem. The leaves are in opposite pairs and their orientation shifts through 90 degrees at alternate nodes along the stem - and so do the lines of hairs between successive nodes.

The other key element of the training was to draw identification features like this. These days, thanks to digital photography, it’s easy to record images of them but a simple annotated drawing is a far more effective way of learning the key differences. It involves careful observation, trying to work out the relationships between parts of the object – you really need to look closely at it and understand it. Which is why – I guess –  this simple ID character to germander speedwell has remained firmly stuck in my brain for four decades.