Mr. Answer Man Please Tell Us: What’s inside lava lamps, and how do they work?
A lava lamp is a decorative tube-shaped light fixture containing a colored, oily fluid that flows up and down throughout the lamp chamber in a manner reminiscent of molten lava. As the fluid rises and sinks in the lamp chamber it changes shape and breaks into globules of various sizes, giving a psychedelic effect of constantly shifting patterns.
Credit for the creation of the lava lamp is given to English engineer Craven Walker who, in the late 1940s, saw a prototype of the lamp in a pub in Hampshire, England. This early version, according to the Walker legend, was made of “a cocktail shaker, old tins and things.” He purchased the liquid-filled fixture and set out to make his own. Walker formed the Crestworth Company in Dorset, England, and over the next 15 years tried to build a better lava lamp.
When first marketed under the name Astro Lite in British stores in the early 1960s, it was not an immediate success. Then, at a 1965 German trade show, two American entrepreneurs saw an early model on display, and bought the rights to manufacturer the lamp in North America. In the United States, they changed the name from Astro Lite, to the infinitely hipper Lava Lite Lamp and began manufacturing operations in Chicago.
With the advent of psychedelia and pop-art later that decade, Walker's gimmicky contraption became a major fad. By the time Walker left the business in 1990, he had sold over seven million of his creations. Today, the company ships 400,000 lamps a year to shops around the world. Currently, Haggerty Enterprises is the only U.S. manufacturer of Lava Lite Lamps and they distribute them nationally through a number of retail and mail order outlets.
The lava effect is due to the interaction between the fluids used in the lamp.
These fluids are selected on the basis of their density so one tends to barely float in the other. In addition, they are chosen based on their coefficient of expansion, so as they are heated one tends to rise or sink faster than the other. When heat from the light bulb warms the heavier liquid sitting on the bottom, it gets hotter and, due to its lower density, rises to the surface.
By the time the “lava” reaches the top of the lamp, it begins to cool, becomes denser, and sinks to the bottom. As the lava sinks, it gets closer to the light bulb, heats up again, and the process is repeated over and over. Therefore, the key to successful lava lamp design is the selection of appropriate immiscible fluids. The exact composition used in lava lamps is a proprietary secret, but in general terms, one fluid is water based and the other is oil based. The aqueous phase may be water mixed with alcohol or other water-soluble solvents.
The second fluid must meet a number of design criteria: it must be insoluble in water, heavier and more viscous, non-reactive and non-flammable, and reasonably priced. It must also be non poisonous, unchlorinated, not emulsifiable in water, and must have a greater coefficient of expansion than water.
While fluid selection does not change from lamp to lamp, there are design changes to be considered because lamps are available in different colors, sizes, and styles.
The original Century model, which is still manufactured today, was the most popular model during the 1960s and 1970s. Its gold base is perforated with tiny holes which simulate starlight and its 52 oz (1.46 kg) globe is filled with red or white lava and yellow or blue liquid.
A number of interesting variations on the Century have been manufactured in past years, although not all of them are still made today. For example, the Enchantress Planter Lava Lite lamp came equipped with plastic foliage. The Continental Lava Lite lamp which, was the only cordless, non-electric model, featured a candle to warm the lava.
The Consort Lava Lite lamp, according to the company's 1970s catalog, was designed with a more masculine look “perfect for the study or den, so right for the executive suite.” There was also the Mediterranean Lava Lite lamp, which was decorated with black wrought iron. In addition, Haggerty offers so-called giant lamps, which range in size up to 27 in (68.6 cm) tall.
The actual ingredients used in Lava Lite Lamps are proprietary but there are several liquid ingredients, which can be combined to give a lava effect.
Lava-type lamps can be made with water mixed with isopropyl alcohol as one phase and mineral oil as the other. Other materials, which may be used as oil phase ingredients include benzyl alcohol, cinnamyl alcohol, diethyl phthalate, and ethyl salicylate.
Other additives used in lava lamp fluids include various oil and water-soluble colorants. The specific gravity of the aqueous phase can be adjusted through the addition of sodium chloride or similar materials. In addition, a hydrophobic solvent may be added to the mixture to help the lava coalesce. Turpentine and similar paint solvents are said to work well in this regard. Antifreeze ingredients can also be added to increase the rate at which the lava warms.
A clear glass cylinder is used to house the fluids and forms the body of the lamp. The classic lava lamp shape is an hourglass about 10 in (25.4 cm) high.
A regular incandescent bulb is used as the source for both light and heat in a lava lamp. The type of light bulb is critical to ensure the lava is not over or under heated. Haggerty Enterprises lists several bulb types that are appropriate for their appliances, depending on which the model: 40 watt frosted bulb, 100 watt reflector bulb with inside frost, 7.5 watt bulb 40 watt candelabra type. Although it does not generate at much heat, a florescent bulb is used in their Pacifica model.
Other items used in lava lamp production include the base plate, which houses the electrical components, 16-gauge lamp wire, and an electrical plug. Quarter inch (0.635 cm) thick foam rubber may be used as a gasket material to seal the chamber. Miscellaneous hardware, such as screws, is also used. Optional equipment, such as a light dimmer switch or a small fan, may be used for temperature control.
The Manufacturing Process
The manufacturing process of the lamp consists of several steps, both automated and manual. According to a representative of Haggerty Enterprises, the company has the capacity to produce up to 10,000 lamps per day on their assembly line.
The glass cylinder is fastened to the ceramic lamp fixture, which forms the base. The lamp is attached to the appropriate wiring and the bulb is screwed into place. The gaskets are glued into place to prohibit leakage. The containers are assembled and checked to make sure they are leak proof.
Compounding liquid phase
The liquid phases are mixed and added separately. Isopropyl alcohol is used to lower the specific gravity of the water phase so the mineral oil floats appropriately. By mixing water and alcohol in the correct proportions, the mineral oil can be made to float. In 90% alcohol, the mineral oil will sink to the bottom.
The addition of 70% alcohol will make the oil seem lighter until it is about to “jump” off the bottom. The correct ratio is about six parts 90% isopropyl alcohol to 13 parts of 70% isopropyl alcohol. Dyes, salt, etc. are then mixed into the water phase, and the oils and waxes are added to the second liquid. Some heating may be required to melt the waxy materials.
The lamps are moved along a conveyor line and first filled with the oil/wax phase, then the water phase. A small air-space of about 1 in (2.54 cm) is left at the top to allow for expansion of the hot liquids. This important because the amount of airspace can influence the size of the bubbles formed by the lava. After filling, the cylinder is capped with either a screw type cap or a bottle cap type, which is crimped into place.
During the batching and filling processes, the liquids are checked to ensure they were correctly manufactured. The proper ratio and composition of the two liquid phases is critical to ensure that the lava effect will be achieved. An incorrect ratio may allow the oil and water phase to mix together, separate into bubbles which are too small, rise and fall as one continuous mass, or become mixed with the water and not separate at all.
It is critical that all electrical connections are good and seals are tight to ensure safety and that there are no leaks. Improper gasket alignment or poor seals can result in leakage of the fluids. After filling, each lamp is checked to ensure the light bulb is completely centered and tightened. The bulb and socket may move slightly during shipping. If so, the owner is instructed to gently push the socket back to the center of base.
Instructions on how to change the bulb are provided inside the lamp socket base. Variation in lamp size or wattage may yield unsatisfactory lava flow and may increase the risk of fire.
During initial use, the lava may not flow properly or may float to the top of the globe. If this happens, the lamp should be allowed to heat up for four hours or more to allow the lava material to become completely molten. Excessive agitation of the lamp may cause the fluids to intermingle and become cloudy, or may even result in permanent malfunction. The lamp should not be stored in direct sunlight as this may cause the colors to fade.
Given the proprietary nature of lava lamps, it is difficult to speculate on future improvements in the manufacturing process.
However, it is interesting to note that computer technology has spawned its own version of the lava lamp - the virtual lava lamp. Also known as the Javalamp after the popular computer language, this virtual lamp is a computer animation that mimics the appearance of the real item.
How Products Are Made / Wikipedia /
Mental Floss / Quora /
Science How Stuff Works / Scientific American / FAQ /
What’s inside lava lamps, and how do they work? (YouTube)
NAVSPEAK aka U.S. Navy Slang
Piped Aboard: (of a CO, VIP or other dignitary) Recognized upon entering a ship or land installation by the Boatswain's Mate blowing 2 notes (low, then high) on a boatswain's pipe, followed by sets of two bells, depending on the rank.
After the musical introduction, the dignitary's rank and sometimes name is announced, followed by “Arriving” or “Departing”.
The Commanding Officer and embarked Admiral are piped aboard with the Ship's name or the Group name.
For other dignitaries, the office is used (e.g. “Department of Defense, Arriving”).
Senior officers may be “bonged on board” as a courtesy; in this case, the introduction refers to their rank and service only, e.g. “Colonel, United States Marine Corps, arriving”.
The CO of the particular ship [and the embarked Flag Officer] or installation gets a “stinger», a single bell ring after “arriving”/“departing”.
Bells may be used alone (without a pipe) in the absence of a boatswain's mate.
Pirate Navy: Small boy crafts generally referring to the smallest of the vessels, such as Minesweepers, Coastal Patrol boats, and sometimes Frigates.
Piss Cutter: A folding uniform cap.
1) A urinal (not a toilet).
2) An unpleasant situation “that's a pisser”.
Where Did That Saying Come From?
“Silence is golden:”
Meaning: A proverbial saying, often used in circumstances where it is thought that saying nothing is preferable to speaking.
History: As with many proverbs, the origin of this phrase is obscured by the mists of time. There are reports of versions of it dating back to Ancient Egypt. The first example of it in English is from the poet Thomas Carlyle, who translated the phrase from German in Sartor Resartus, 1831, in which a character expounds at length on the virtues of silence:
“Silence is the element in which great things fashion themselves together; that at length they may emerge, full-formed and majestic, into the daylight of Life, which they are thenceforth to rule. Not William the Silent only, but all the considerable men I have known, and the most undiplomatic and unstrategic of these, forbore to babble of what they were creating and projecting. Nay, in thy own mean perplexities, do thou thyself but hold thy tongue for one day: on the morrow, how much clearer are thy purposes and duties; what wreck and rubbish have those mute workmen within thee swept away, when intrusive noises were shut out! Speech is too often not, as the Frenchman defined it, the art of concealing Thought; but of quite stifling and suspending Thought, so that there is none to conceal. Speech too is great, but not the greatest. As the Swiss Inscription says: Sprecfien ist silbern, Schweigen ist golden (Speech is silvern, Silence is golden); or as I might rather express it: Speech is of Time, Silence is of Eternity.”
That fuller version - 'speech is silver; silence is golden', is still sometimes used, although the shorter form is now more common.
The same thought is expressed in a 16th century proverb, now defunct - as many present-day feminists would prefer it:
“Silence is a woman's best garment.”
Silence has in fact long been considered laudable in religious circles. The 14th century author Richard Rolle of Hampole, in “The psalter; or psalms of David”, 1340:
“Disciplyne of silence is goed.”
Wyclif's Bible, 1382 also includes the thought:
“Silence is maad in heuen.”
Bizarre News (we couldn’t make up stuff this good - real news story)
Magnetic field at Martian surface ten times stronger than expected
Source: University of British Columbia
Summary: New data gleaned from the magnetic sensor aboard NASA's InSight spacecraft is offering an unprecedented close-up of magnetic fields on Mars.
In a study published in Nature Geoscience, scientists reveal that the magnetic field at the InSight landing site is ten times stronger than anticipated, and fluctuates over time-scales of seconds to days.
“One of the big unknowns from previous satellite missions was what the magnetization looked like over small areas”, said lead author Catherine Johnson, a professor at the University of British Columbia and senior scientist at the Planetary Science Institute. “By placing the first magnetic sensor at the surface, we have gained valuable new clues about the interior structure and upper atmosphere of Mars that will help us understand how it - and other planets like it - formed.”
Zooming in on magnetic fields
Before the InSight mission, the best estimates of Martian magnetic fields came from satellites orbiting high above the planet, and were averaged over large distances of more than 150 kilometres.
“The ground-level data give us a much more sensitive picture of magnetization over smaller areas, and where it's coming from”, said Johnson. “In addition to showing that the magnetic field at the landing site was ten times stronger than the satellites anticipated, the data implied it was coming from nearby sources.”
Scientists have known that Mars had an ancient global magnetic field billions of years ago that magnetized rocks on the planet, before mysteriously switching off. Because most rocks at the surface are too young to have been magnetized by this ancient field, the team thinks it must be coming from deeper underground.
“We think it's coming from much older rocks that are buried anywhere from a couple hundred feet to ten kilometres below ground”, said Johnson. “We wouldn't have been able to deduce this without the magnetic data and the geology and seismic information InSight has provided.”
The team hopes that by combining these InSight results with satellite magnetic data and future studies of Martian rocks, they can identify exactly which rocks carry the magnetization and how old they are.
Day-night fluctuations and things that pulse in the dark
The magnetic sensor has also provided new clues about phenomena that occur high in the upper atmosphere and the space environment around Mars.
Just like Earth, Mars is exposed to solar wind, which is a stream of charged particles from the Sun that carries an interplanetary magnetic field (IMF) with it, and can cause disturbances like solar storms. But because Mars lacks a global magnetic field, it is less protected from solar weather.
“Because all of our previous observations of Mars have been from the top of its atmosphere or even higher altitudes, we didn't know whether disturbances in solar wind would propagate to the surface”, said Johnson. “That's an important thing to understand for future astronaut missions to Mars.”
The sensor captured fluctuations in the magnetic field between day and night and short, mysterious pulsations around midnight, confirming that events in and above the upper atmosphere can be detected at the surface.
The team believe that the day-night fluctuations arise from a combination of how the solar wind and IMF drape around the planet, and solar radiation charging the upper atmosphere and producing electrical currents, which in turn generate magnetic fields.
“What we're getting is an indirect picture of the atmospheric properties of Mars -- how charged it becomes and what currents are in the upper atmosphere”, said co-author Anna Mittelholz, a postdoctoral fellow at the University of British Columbia.
And the mysterious pulsations that mostly appear at midnight and last only a few minutes?
“We think these pulses are also related to the solar wind interaction with Mars, but we don't yet know exactly what causes them”, said Johnson. ”Whenever you get to make measurements for the first time, you find surprises and this is one of our 'magnetic' surprises.”
In the future, the InSight team wants to observe the surface magnetic field at the same time as the MAVEN orbiter passes over InSight, allowing them to compare data.
“The main function of the magnetic sensor was to weed out magnetic 'noise', both from the environment and the lander itself, for our seismic experiments, so this is all bonus information that directly supports the overarching goals of the mission”, said InSight principal investigator Bruce Banerdt of NASA's Jet Propulsion Laboratory in Pasadena, California. “The time-varying fields, for example, will be very useful for future studies of the deep conductivity structure of Mars, which is related to its internal temperature.”
Science Daily (02/24/2020)