Monday 29 February 2016

Purple-crested Turaco (Lourie)

While growing up I never saw louries (turacos) in our garden, but over time the bird populations changed and for about the last ten years I lived there Purple-crested Turacos (Tauraco porphyreolophus) often visited our garden.  I saw two together fairly often so there was at least a pair of them.

Their call is an unmistakable repeated kok-kok-kok sound which my wife describes as laughing. They are shy and fly from tree-to-tree, hopping between the branches, mostly hidden in the foliage. When they fly their crimson red flight feathers are dazzling.

With their loud call you are left in no doubt about where they are. However trying to see them for a good photograph with hopefully all of the bird and not in dark shade drove me crazy. I finally got some decent pictures when one stayed out in the open on an old avocado pear tree for a moment, rather than buried in our enormous Forest Natal Mahogany Tree (Trichilia dregeana).


Friday 26 February 2016

Helmeted Guineafowl

Helmeted Guineafowls (Numida meleagris) are common in South Africa, this particular one photographed, like the previous few posts, in the West Coast National Park. I love their spotty plumage.



Origin of the names

 

The origin of the name guineafowl and it's species name meleagris is interesting.

The guineafowl was domesticated in classical times in Greece and were called melanargis meaning black & silver which was corrupted to meleagris.

They were distributed throughout the Roman Empire as were the Moroccan Guineafowl subspecies (N. m. sabyi). The Romans also called the former species meleagris and the latter the numidian fowl or hen. N. m sabyi has possibly been extinct since the 1950s.

Both disappeared from Europe after the Roman Empire declined. Guineafowls were rediscovered by the Portuguese explorers on the west coast of Africa in the late 16th century which is where they get their modern common name guineafowl

The naming of the wild turkey from North America (Meleagris gallopavo) intertwined with the guineafowl (Numida meleagris) but from what I've read it seems rather murky with multiple theories.

They both share the word meleagris, one as its genus the other as its species. The guneafowl obviously had that name first, but the puzzle is why did the turkey get it too. One theory is that they appeared in the European market at around the same time with resulting confusion.

While the scientific name link is obvious, the common name turkey doesn't escape either.

One theory is that merchants from the Ottoman Empire traded in guineafowl and that the birds got a nickname of turkey. Settlers in North America saw what seemed to be similar birds and then called them turkeys. Another theory is that merchants from the East also sold turkeys later... A further theory on Wikipedia is that they were named turkeys just because it was an exotic place like Guinea which seems unlikely, but I suppose weirder name choices have been made with less basis.

References


Turkey name theories:
  1. The flight of the turkey, The Economist, 20th December 2014
  2. Guinea Fowl, Roy Crawford in Poultry Breeding and Genetics Elsevier, Amsterdam, 1990
  3. http://www.npr.org/templates/story/story.php?storyId=97541602
  4. Helmeted Guineafowls, Wikipedia
  5. Wild Turkey, Wikipedia
Other:
  1. Guinea Fowl, Roy Crawford in Poultry Breeding and Genetics Elsevier, Amsterdam, 1990
  2. Extinct Birds, Julian P. Hume, Michael Walters, 19 Feb 2012
  3. Helmeted Guineafowls, Wikipedia
  4. BirdLife International, Helmeted Guineafowl Numida meleagris

Yellow Bishop

Here is another bird photographed in the West Coast National Park in South Africa. It is a Yellow Bishop (Euplectes capensis) which is a species of weaver (Ploceidae).


Thursday 25 February 2016

Bokmakierie

A Bokmakierie (Telophorus zeylonus) in the West Coast National Park with an insect. Bokmakieries are a species of bushshrike endemic to Southern Africa.

The West Coast National Park is a very beautiful nature reserve about an hour's drive from Cape Town. It borders Langabaan Lagoon on the one side and the Atlantic Ocean on the other. The best time to visit is in August or September when the flowers are in full bloom and the private land north of the reserve is opened for visitors.


Praying Mantis

This impressive praying mantis was hanging onto the top of a window-frame. I'm not sure what it is but it looks like one of the African Stick Mantis species (Hoplocorypha)

There are more than 200 species of mantis in sub-Saharan Africa.


Sunday 14 February 2016

Common Hairtail Butterfly

I photographed this Common Hairtail butterfly (Anthene definita definita) drinking water and minerals from the mud on a farm road in the Karkloof Mountains. Its wingspan is between 25-28mm.

A good tip I learn't when I was a kid photographing my dog was to always photograph animals at their level -- even if that sometimes means lying down in the mud in a tractor rut, or in the case of my dog being pounced upon and having my face licked.



Saturday 13 February 2016

Phantom Flutterer

The Phantom Flutterer (Rhyothemis semihyalina) is a very beautiful dragonfly that occurs throughout Africa, the Indian Ocean islands, part of the Middle-East and part of southern Asia.

The iridescent purple is fantastic - the close-up photograph beneath this one shows it better although a photo doesn't do it enough justice. I've rarely seen this dragonfly but I was lucky enough to photograph this one right next to my front door. I can sprint for a camera quite fast!



Friday 12 February 2016

Gaudy Commodore Butterfly

This is a Gaudy Commodore butterfly (Precis octavia sesamus) in its winter form photographed in my garden. Its summer form is red with black markings.

It's a large butterfly that I've always found hard to photograph as it's quite skittish (well at least around me!) unless you come across it early in the morning while it's still cold outside.


Thursday 11 February 2016

GPO No. 309 Telephone (Siemens)

My wife has a British GPO No. 309 telephone manufactured by Siemens in the UK that was used in South Africa.

The 300 series telephones were manufactured between 1937 and 1959 for the British GPO although production seems to have continued longer for UK associated markets such as South Africa, Australia, etc...


 It still works fine except for the obsolete pulse dialing. The only repairs I needed to make was to heat shrink over where the fabric cable had frayed back from the handset and the wall socket end. I was interested in putting a pulse to tone dialing converter in it but my wife preferred it to remain unchanged and used for receiving calls and most certainly hearing them!

The phone has three distinct parts from bottom to top: A heavy ballasted base plate, a bell-set and the actual phone.

Phone -- Dial and Handset

 


The pulse dial mechanism is in the top-center in the photo above. After the dial is turned it is returned to its resting position by a spring at a constant rate regulated by a centrifugal governor device. It is the horizontal device near the top of the picture with a circular brass housing on the right-hand side. It has a worm-gear rod that goes to the left and engages with the gear that is visible there.

The leaf spring contacts produce the pulses by disconnecting the direct current of the line briefly between one and ten times. The voltage on the line is negative in relation to ground to help prevent corrosion. 

The leaf springs parallel and nearest to the terminal block at the bottom are for disconnecting the line when the handset is on-hook. There is a vertical metal spike that is just visible above the contacts which drives down between them when the hook is depressed to disconnect them.

I think the large electronic part on the right-hand side is an inductor.

Bell-Set

 

The bell-set is in the rectangular box and is wired to the phone above it by an external cable. This was required as it separates off the phone into a stand-alone unit with the intention that people might like to have it located somewhere else, like a hallway, so that it could be heard throughout the house. It is very loud so unsurprisingly from what I've read it seems most people just wanted it connected together.


The bell-set has two different sized bells struck by a ball-shaped hammer in-between them, driven by an electromagnet. This gives it a beautiful two-tone ring that sounds much better than the vintage-phone ringtones on smartphones ...  more menacing ... like if you don't answer it will rip your face off, but in a beautiful way.

The white block at the bottom of the bell-set photo is a capacitor. It blocks the direct current and allows through the alternating current of the ringing signal sent by the exchange.

Ballast Plate


The very heavy ballast plate beneath the already heavy bell-set seems overkill so I would guess it might have been attached directly to the lighter phone when the bell-set was elsewhere. On the ballast plate there is a wiring and parts diagram:



The handset has an interesting old moving iron speaker. The cover unscrews to reveal a metal disc which can be slid carefully off horizontally. It is held in place by permanent magnets underneath it and driven by a solenoid. 

Microphone

 

 

Microphone Housing

 



The microphone's cover also unscrews to reveal a microphone unit that is simply resting on spring contacts and so will just drop out. It also contains the screw terminals for the handsets wiring.

If you ever come across an old telephone like this for sale I would strongly suggest buying it. If nothing else it could be converted into a fantastic alarm clock! Perhaps you could set the time using the dial and turn off the alarm by raising and lowering the handset?

Friday 5 February 2016

Moss under a Microscope

Moss from a path in my garden under a microscope with grains of fine sand. This photo was taken with a USB microscope I bought from Adafruit that I used to inspect circuit boards.

My father has now adopted it as it turns out it is brilliant for looking at postage stamps for the little differences that philatelists need to spot. All his friends at his stamp club have been buying USB microscopes since he showed them. Better to look at a nice large screen than squint through a magnifying glass...

A circuit board using the same microscope at a lower magnification: