Introduction.

Named for the Earl of Orrery who, at the beginning of the 18th Cent. in Ireland, had one made for his personal collection of scientific apparatus. Orreries are three dimensional models of how celestial bodies orbit the Sun in our solar system.

They may be exceedingly complex or very simple, finished with precious stones and gold, or made from wood and paper.

They featured in the collector’s cabinets of the 18th and 19th Century. Some were made for Kings, heads of State and wealthy patrons. Itinerant philosophers carrying orreries travelled through the educated and enlightened world of the time.

“The wise man looks into space and does not regard the small as too little

nor the great as too big, for he knows that there is no limit to dimensions.”

Anon.

Brian Greig.

Since the age of fourteen Brian has been making telescopes and observing the sky.

He was fortunate in having an Uncle who built a 300 mm diameter. reflecting telescope
and an observatory to house it.
In effect Brian became the sorcerer's apprentice.

An abiding interest in antique scientific instruments also began at this time and continued through a life-time spent in design, development and research into military hardware in England, Canada and Australia.
Since his retirement in 1990 he has devoted his time once more to the sky above, and the antique instruments used in telling its secrets.

He is an accomplished public speaker and has appeared on Good Morning Australia and radio. The author of numerous articles on astronomy he has spent the last 4 years on research for a book about the Great Melbourne Telescope and the history of astronomy in Victoria, visiting Ireland, England and Europe in the process.

His book “Halley’s comet over Australia” published in 1986 sold over 60,000 copies and was entered in the Guinness book of records as being the fastest book ever published in Australia.

What did Brian make for Sydney Observatory?

Brian made 2 astronomical models for the Sydney Observatory. These were designed to be powered and operated around the clock by visitors of all ages. In order to stand up to this heavy workload, the gears had to be made especially thick.

Brian Greig's Electric Tellurian at Sydney Observatory

The first model was a hybrid Tellurian / Lunarium - an elaborate Sun/Earth/Moon system. It is a Tellurion (sometimes also spelt Tellurium) because it shows the Earth rotating anti-clockwise on its axis as it revolves anti-clockwise around the sun.

The sun includes a lamp which lights up the side of the Earth facing the sun, thus demonstrating day and night and how the sun rises in the east and sets in the west. The apparent motion of the stars can also be understood via the rotation and revolution of the Earth.

The model is also a Lunarium...

The north and south poles of the Earth are on a constant tilt as the Earth revolves around the sun, demonstrating the position of the north and south celestial poles, the significance of the zodiac and the occurence of seasons.

The model is also a Lunarium because it shows the moon revolving anti-clockwise around the Earth. This coupled with the light from the sun shows the phases of the moon - full moon (as viewed from Earth) when the Earth is between the sun and the moon, and new moon when the moon is between the sun and the Earth.

The moon's orbit is on a tilt, which explains why we do not get a lunar and solar eclipse every full moon and new moon respectively, but only when a full or new moon occurs as the moon is crossing one of the nodes - the points halfway up or halfway down the tilting orbit.

The angle of the tilt can be adjusted manually every year by the exhibitors to correct for the clockwise recession of the nodes.

The second model was a standard Brian Greig Orrery featuring all of the planets out to Saturn with no gearing for the moons. Brian made some improvements in design, to help it withstand the stresses of constant use.

How does Brian create an Orrery?

An Orrery can take Brian anywhere from 6 weeks to 6 months to make. Although Brian has now made more than a dozen of these clockwork models, the process still requires great patience and precision.

Potential customers are invited to see photos of Brian's orreries. The customer may request certain features to be added to previously created designs. They may request additional planets or revolving moons etc. Brian then spends a few weeks considering the implications of the new design requirements before he puts together a quote. The quote includes time estimates for design, new tool sourcing, construction and components.

Don't forget to view the exquisite orrery catalogue with items that are for sale.