Silver lining
Evan Zabawski | TLT From the Editor December 2019
From bearings to boll weevils.
The term is commonly expressed as 'every cloud has a silver lining,' not 'every bearing.'
Photo courtesy of the National Agricultural Library, Agricultural Research Service, U.S. Department of Agriculture.
During a recent class I was discussing common sources of silver detected by in-service fluid analysis. While some older oil coolers might have been brazed with solder containing silver, the most common example given is aviation bearings and Electro-Motive Diesel locomotive engine wrist pin bearings and turbocharger bearings.
The explanation for such a material choice in bearings is quite simple: coating steel rolling element bearings with silver makes them substantially stronger and able to function at high temperatures and also acts as a lubricant to increase performance and add a critical margin of safety. If an airplane experienced an oil pump failure, the bearings have a long enough run-dry capability for the pilot to safely shut down the engine without incurring substantial damage and then perform a dead-stick landing.
This logic does not seem to apply to locomotives, however, since the driver can simply move the throttle to an idle position and let the train coast while shutting down the engine; notwithstanding the fact that wrist pin bearings are typically journal bearings and that many of these engines are used in stationary applications like standby generators. Why silver is used still pertains to marginal lubrication conditions, albeit from frequent engine starts and not oil pump failures, and high temperatures due to combustion.
After I finished the explanation, a student asked, given my propensity for injecting tidbits of etymological trivia, if this is where the term “silver lining” originated. The term not only predates engines and bearings but is commonly expressed as “every cloud has a silver lining,” not “every bearing.”
The origin of the term seems to be 17th Century poet John Milton’s masque Comus. A masque was a contemporary form of theater entertainment involving poetry, music and dancing by masked actors. Comus contains a scene with a lady left alone in a forest, and as night falls she prays for deliverance; her ladyship believes her prayers to be answered by a promising omen: “Was I deceiv’d, or did a sable cloud turn forth her silver lining on the night? I did not err, there does a sable cloud turn forth her silver lining on the night and cast a gleam over the tufted grove,” referring to the gleam of moonlight on the edge of dark thunder clouds, hinting at a clearing of the skies.
Over the next two centuries this passage was referenced in literature like Charles Dickens did in Bleak House when his character Mr. Skimpole remarks, “I turn my silver lining outward like Milton’s cloud.” Later, Victorians adopted the more proverbial phrasing “there’s a silver lining to every cloud” and before long settled on its current form.
While researching this etymology, I stumbled upon a prime example (involving the boll weevil) that somewhat happens to be celebrating its 100th anniversary this month. The boll weevil lives almost exclusively on cotton plants and appeared in Coffee County, Ala., in 1915, causing an immediate loss of two-thirds of the annual cotton crops and eventually decimating cotton yields in some areas over the next three years.
In 1916 local businessman H.M. Sessions, who felt peanuts could thrive in this region, convinced cotton farmer C.W. Baston to use Sessions’ peanuts to plant a crop. The first crop earned $8,000, enough to get Baston out of debt, and provided seed for other eager farmers wishing to enter the peanut business. Farmers continued to grow cotton but learned to diversify their crops, thus bringing prosperity back to the county as the largest producer of peanuts in the country and the first in the region to produce peanut oil.
Another local businessman, Bon Fleming, conceived and helped finance the construction of The Boll Weevil Monument on Dec. 11, 1919, in downtown Enterprise, Ala., “in profound appreciation of the Boll Weevil and what it has done as the Herald of Prosperity,” a clear example that every cloud really does have a silver lining.
Evan Zabawski, CLS, is the senior technical advisor for TestOil in Calgary, Alberta, Canada. You can reach him at ezabawski@testoil.com.