04 September 2018

Book Review: Who was Ingen Housz Anyway? by Norman and Elaine Beale

This short book is a wonderful introduction to the life and times of Jan Ingen Housz.

While the main body of the book is only 36 pages, the authors have packed in a great deal of information and interesting illustrations and photographs. Beginning with the origin of the Ingen Housz surname along with Jan's birth and situation, the book progresses with Ingen Housz's rise as a smallpox inoculator and the lifelong friends he makes along the way.

From being headhunted by royalty for his expertise in innoculation to eventually self-exiling himself back in England during the time of revolution - and violence - on the continent, this man had a colourful life. But that's just some of what happened to him, not the things he did.

The book goes on to explain the experiments that are the foundation of what we understand about photosynthesis and the role of carbon dioxide in the creation of organic matter.

The book concludes with the memorial in St. Mary's Church in Calne that occurred in 1956 and describes the plaque placed there in Ingen Housz's honour.

I really enjoyed reading this book, it was long enough to get across a lot of information, but not so long as to get bogged down in too much detail.

I don't know if the book is still available for purchase, but at £4 a copy with the proceeds going towards the upkeep of St. Mary's Church, Calne, it's definitely worth buying. Otherwise, it's available to loan from Wiltshire library.

30 November 2017

Tree Flowers: November 2017: Lime (Tilia Species)


Pollen deposits found from pre-historic lime blossom has revealed that the small-leaved lime was once the most common tree in lowland England. However this wasn't the case for long as the tree cannot produce fertile fruit below a mean average summer temperature of around 20 degree Celsius. This drop happened around 3000BC in England meaning that the lime tree was stuck wherever it had already occupied. These places became fewer as woodland was cleared and the lime was then used for coppicing.

Species of Tilia remain popular amenity trees, planted in many communal places, such as parks and tow roadside verges. We even have a circle of lime trees in a nearby housing estate.

There are three lime trees in Britain (often called Linden trees in other parts of the world), with the small-leaved and large-leaved lime being the parents of the fertile common lime. The large-leave lime remains quite a rarity, with the other two being much more common.

Lime trees can persist almost indefinitely via the wonders of coppicing, via which the tree provides 'bast' (the origin of names such as Bastwick in Norfolk), which is the inner bark from young poles for making rope and fabric fibres. But historically, the lime has also been used for wood carving.

Westonbirt Arboretum in England has a coppice of limes that has been estimated to be around 2000 years old and can be seen in the photo below.

But what I really like of the lime is the bract that hovers over the flowers making it clear to the world that it is, indeed, a lime tree.

The flowers mature at different times, so you'll be able to see buds as well as fully open flowers.

Each flower contains both the male and female parts, with the petals being a greeny-yellow colour. The flowers hang in clusters ranging in number from around 4 to 10. The pale filament provides a good contrast to the bright yellow anther, all of which surround a robust stigma.


Because the bract is so easy to see, even from a moving car, I enjoy looking for the flowers each year, which tend to arrive by mid-summer. I'm very much looking forward to observing the flowers again next year.


References:
Mabey, R. (1996) Flora Britannica. 1st edition. London: Chatto & Windus / Sinclair Stevenson.
More, D. and White, J. (2012) Illustrated Trees of Britain and Northern Europe. London, UK: A&C Black.