Reginald's Letter:
Note: "Uncle Ben" was the pen name of the editor of a column in The Weekly Times.
Reginald Harvey, who lives at Lamplough, via Avoca, writes:
1. Reginald and daughter Maureen standing by their truck loaded with eucalyptus leaves.
2. The truck under the hoist on the still.
3. The boiler shed.
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Dear Uncle Ben,
I saw in the Weekly Times that you were offering a prize for any subject published this month. I will take for my subject
"The process of extracting the eucalyptus oil from gum leaves."
Well, first of all you go to a paddock where young bushes are growing, cut down a generous quantity, carry them into heaps and sickle them (i.e. cutting the leaves off the stems with a sickle). When you get a vat cut, the dray comes (Photo 1) and your leaves are carted to the plant nearby, where they are emptied (Photo 2).
The plant consists of a portable steam engine, vat, condenser and oil container (Photo 3). The engine has an inch pipe screwed into the upper portion of the boiler, and this pipe passes down to the bottom of the vat. The vat is made of pine and is some 8 feet deep and 4 feet in diameter. The pipe is showing in the bottom of the vat six inches.
The leaves are then forked into the vat and tramped down. The lid of the vat is then let down by means of a crane. This lid is very heavy as it has to stand a heavy pressure of steam. The lid is then plastered over to avoid any steam escaping. The dome is then inserted into the hole in the lid. The dome passes from the vat into the condensing pipes which are some hundreds of feet in length and under two or three feet of water (cold). |
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The steam is then turned on, and it passes from the vat through the through the inch pipe leading from the vat down to the bottom of the vat. It spreads right through the leaves and gradually works its way upwards. Only 20-30 pound of steam is needed. When the steam gets to the top of the vat it passes through the dome to the condensing pipes, not as it came from the vat, but with the eucalyptus with it. When the steam reaches the condensing pipes it strikes something cool, and by the time the last length of piping is reached it is cold water, and in this form it runs into the container. It is only the colour of rain water, but it is oil and water mixed.
When it runs into the container, the water goes to the bottom and the eucalyptus oil floats on the surface. A thick scum forms between the water and oil and thus the water can be easily distinguished from the oil. the oil is then allowed to run off the top of the container into a kerosene time, and the water runs out the outlet pip at the bottom. The oil is then put into drums and sent to the refinery where it goes through a further process of refinement.
Age 12 years and 11 months.
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You have sent an interesting letter, Reginald, and I shall be please to hear from you again.
- Uncle Ben
Article prepared by Harry Gardner for Australian Tradition, 24/10/2001
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