Before I write anything in this post, I consider it obligatory on my part to mention the source of the following Information. I concede that all the little stuff that I have learnt about Heron comes from Mr Michael Lahanas’ Website ( http://www.mlahanas.de ). A physicist extraordinaire , Michael maintains an excellent website which deals with all the historical information about Greece, be it ancient, medieval or modern. Many thanks to his efforts and research in putting forth so much information about this little known scientist. All the information about Heron is available on his site : Link

In some of my previous entries, I have discussed about Heron’s crude steam engine. Heron, an extraordinary Mechanic and inventor, probably understood much more than what we attribute to ancient generation. This is a mechanism for opening Temple doors built by Heron:

As observed, Heron knew that Air was matter and that it expanded on heating. This is a simple mechanism he developed for opening Temple doors. When altar was heated , air expanded pushing out the water from the reservoir into the bucket. Growing weight of water in the bucket pulled up the mass on the left revolving the hinged doors in the process. Brilliant !

Heron, more of an engineer than a scientist, built many more machines which reflect his deep understanding of Mechanics and Physics. As is demonstrated in this following video ( again courtesy the above mentioned site), the intellect of Heron was put to use by the powerful brass in religion and army. His inventions are mostly restricted to Artillery and those made to amuse devotees at the temples. Interested may look at this link to know why these machines were not put to use and led to the revolution that it should have otherwise ( Social and political reasons ).

I am currently reading about Hero’s inventions (Reference is mentioned on the currently reading page on the blog ). A possible challenge would be to document all the important and interesting inventions here with mathematical analysis ( a reasonable problem being calculating efficiencies and simple applications of each of these mechanisms). Since most of these inventions are redundant today, in my perspective, understanding them would probably help a student like me in developing a structured thought process that goes in while designing machines or mechanisms ( I admit I haven’t really learnt anything new here ! ).

Comments welcome !

Here’s an informative video about Hero’s inventions and how they were put to use ( better read as misuse ).

1. The Barus Effect (extrudate swell)

2. The Weissenberg Effect (rod-climbing) : Generally we would observe a vortex when we swirl a liquid like water as it dips but here this  stuff behaves very strange . It climbs up the drill !

3. The Kaye Effect (liquid leaping sideways) . A very very interesting video through a High Speed Cam is available below . The experiments that I read about about this effect were done with the hair Shampoo that is used commonly.

What is Aeolipile ?

The word means “Wind Ball” in Greek. What hero did was very simple. Take a closed vessel , fill it with water. Heat it.Now what do we have , Steam of course. Let it pass through two vertical outlets into a Ball which can rotate. To create a torque on this Sphere (which has to be fixed so that it can rotate about the pivot). Place two vents opposite diametrically and lo ! the ball will rotate due to the torque generated.

No Rocket Science , You’d say ! But that’s the same principle behind today’s Rocket !!! Aint’t it ? . Beautiful conversion of Thermal Energy to useful mechanical Shaft rotation.

Hats Off ! Mr Heron !

Hero apparently did not use it much ; It was a more of a fancy toy , says history . Sad. Some articles on the net say he used it to open doors at Temple (How ?! and Why Temple doors ? ). This is the same principle behind the steam engine.

A step by step procedure to create Heron’s Aeolipile is available at this link ( I did not really have the patience to go through it Call it the initial poor “oh this is so simple for me” attitude) : http://www.instructables.com/id/Ancient-Aeolipile–steam-engine%2c-and-magnets-for-g/

Complete detailed Analysis which I plan to study soon is available at http://www.mlahanas.de/Greeks/HeronAlexandria.htm Here’s a nice video . How I wish we could do projects like these at school instead of boring theory !

I must say , this blog was some find in these December Holidays. Voted the Second best Tech Blog in India after Indibloggies 2006, The blog not only has Technical writings ( Fluid Sciences, Mechanical Engg, Chemical Sciences  et al ) but some very enjoyable, intriguing and Informative takes on Issues in IIT , Academia and Research.

This blog catered to Something what I always wanted to know ! A prof’s viewpoint on Student related Issues and the so called (by some) the perennial Professor-student Divide !

Here’s the link: http://www.nonoscience.info/

And Some Interesting Posts :

1A.Top 20 lies by young faculty at IIT : http://www.nonoscience.info/2007/06/21/top-twenty-lies-by-young-faculties/

1BHow to stay calm when interacting with a bunch of idiots, who are otherwise intelligent?

2.Should an IIT prof blog ? 

3. IIT Chennai professors are no more knowledgeable than their students?

4.In Search of a Research Culture

5.Publish or Plagiarize, else Perish

Looks like it can be used in Watches ! Isn’t it ? Regular Circular Periodic motion . here’s the Wiki article : http://en.wikipedia.org/wiki/Geneva_drive

I also plan to read this pdf soon  ( gives the complete analysis of the mechanism) .

And Why on earth am I blogging on Gear Ratio ?

Nearing the end of 3rd Sem , I felt a dire need of documenting and saving the vast lots of interesting stuff (and sometimes mundane) that we learn in our course work. A place where I can refer back and in the process , if possible , share my knowledge and know how and errors therein. This being a technical blog, I do not expect that many will be interested and would participate. But even if I am able to just store chronologically and systematically whatever little interesting stuff that I come across , the blog will serve its purpose !

Cheers !!