How Does Aspirin Find a Headache? (19 page)
Read How Does Aspirin Find a Headache? Online
Authors: David Feldman
Sometimes it costs more to build in a straight line. For example, if a mountain happens to lie right in the middle of a proposed route, a consultation with engineers will reveal quickly that it is cheaper to direct the highway around the mountain than it is to level the natural formation.
If housing or commercial buildings are in the path of the “straight line,” then it may be cheaper to lay extra cement and reduce the cost of buying out the more expensive land. Community opposition has killed more than one proposed highway, but evacuating dwellers and leveling buildings is not only a public relations disaster—it can be an economic one. As communities protest, delays create cost overruns.
Increasingly, environmental factors determine the curvature of a highway. Joan C. Peyrebrune, technical projects manager for the Institute of Transportation Engineers, told
Imponderables
that while highway officials have always been concerned about the impact of new highways upon existing houses and businesses, they are now equally aware of how highways might affect wetlands, parklands, wildlife habitats, etc.
If topography, economics, or community pressure necessitates curves in the highway, engineers are first concerned about safety. Peyrebrune notes that many studies have been conducted about the relationship between the radius of curvature and what speeds can be navigated safely on roadways. The American Association of State Highway and Traffic Officials publishes tables that determine the proper speed limits for given radii of curvature and slopes of highways.
Thomas Deen, executive director of the Transportation Research Board of the National Research Council, provided us with a “philosophy of curvature” that echoed our other sources:
The alignment should consist of long, gentle curves with straight tangent sections for passing on two-lane roads. The design speed of the highway is the limiting factor on the minimum radius of curvature, but the alignment should if at all possible incorporate flat, long curves with the smallest central angle. The alignment should be consistent and not incorporate short, sharp curves with long, straight tangent sections. The choice of highway alignment is made to facilitate the motoring public’s trip from one location to another in a safe, efficient, and pleasing manner.
Properly designed curvature doesn’t render a highway less safe than a straight roadway. In fact, Peyrebrune indicates that “curvature of highways is preferred to long, straight stretches by most motorists,” who can be lulled into obliviousness by the dullness of a straight route.
We have learned quite a bit about how to construct highways in the last few hundred years—it wasn’t always a science. Thomas Werner, director of the traffic engineering and safety division of the New York State Department of Transportation, explained to us how one city wound up with its “distinctive” asymmetrical street structure:
In colonial Boston, cattle once roamed the city. Where they trampled the grass and wore a path, colonialists used the trail to transport goods from one point to another. These cow paths soon became the basis of the city’s street network.
Evidently, colonial cows didn’t walk in a straight line, either.
Submitted by Rory Sellers of Carmel, California
.
We have always been a tad suspicious about the pretensions of wine connoisseurs, and we, too, have wondered whether the “flute” glass for champagne truly enhances the taste of the bubbly wine. We were shocked when we found out that Riedel, the Austrian specialist in glassware for wines, now sells twenty-three different glass types—each is designed to be used with one particular variety of wine.
To help answer this Imponderable, we contacted Pat McKelvey, librarian of the Wine Institute in San Francisco, California. She told us that appropriate glassware meets three criteria:
1) It is thin and clear, to best show off the beauty of the wine.
2) Its shape is best suited to enhance and accentuate the natural bouquet of the wine.
3) Perhaps most importantly, the shape of the rim should direct the wine onto the appropriate portion of the tongue.
Our tongues are full of taste buds—four distinctive types. The buds at the tip of the tongue are most sensitive to sweetness; the buds at the edges are most sensitive to salt (which is why we put salt on the edges of tequila glasses); the buds at the sides of the tongue are most sensitive to acidity; and the buds at the back of the tongue are most sensitive to bitterness. Until recently, most glassmaking technology has focused on designing the appropriate shape and size of the bowl of the glass. The deep, narrow champagne flute was designed to conserve and accentuate the bubbles; the wide burgundy glass, tapered at the top, attempted to catch and release the fruity aroma, while letting in as little ambient air as possible that might dissipate the wine’s character.
But even if the bouquet were enhanced by the shape of the glass, it meant little if the wine didn’t
taste
better; this is why the emphasis, increasingly, is on “rim technology.” In a young burgundy, for example, the high acid level can sometimes overcome the desired fruity taste. The solution, in this case, was to flare the rim so that the wine hit the tip of the tongue, which detects the sweetness of the grapes.
Some wines tend to become unbalanced, with the acid/fruit quotient at one extreme or the other. This is one reason why wine lovers swirl the filled glass. A cabernet Sauvignon glass is wide, so that swirling will blend the flavors more easily. The mouth of the glass is narrow, so that when you drink from it, the liquid hits the middle of the tongue. The proper cabernet Sauvignon glass is designed to hit all four types of taste buds each time you take a swallow.
Riedel has changed the shape of the classic German Riesling glasses. Riesling used to be sweeter, so glasses were designed to direct the wine to the sides of the mouth, where the buds would detect acids more acutely. But now that vintners have made German Rieslings more dry by introducing more acids into the wine, Riedel’s glass has an out-turned rim, in order to guide the wine directly to the tip of the tongue, where the wine’s sweetness will be perceived first.
Riedel tests the efficacy of its designs by conducting blind taste testings, in which the same wine is poured into many different glass configurations. If the “right” glass is not preferred, then Riedel knows it’s time to go back to the drawing boards.
Of course, if your preference is for wine that comes in screw-top bottles, disregard the foregoing.
Submitted by Adrienne Ting of Laguna Hills, California
.
Staling bread is a perfect example of reversion to the mean. Bakery consultant Simon Jackel told
Imponderables
that the typical soft bread contains 32 to 38 percent moisture. If the bread is left unwrapped and exposed to the elements, it will become hard when it lessens to about 14 percent moisture.
Why does the bread get stale and lose the moisture? Although food technologists don’t fully understand all the causes, a process called “retrogradation” occurs, in which internal changes take place in the starch structure. Although bread items are formulated to have a softer crumb portion than crust area, during retrogradation some of the crumb moisture migrates to the crust, which results in the softening of the crust and a hardening of the crumb.
Tom Lehmann, of the American Institute of Baking, adds that as the bread retrogrades, “a portion of the starch in the flour undergoes a gradual change, known as “crystallization,” which results in a gradual firming of the bread. Some of the edible ingredients in the dough, such as enzymes and monoglycerides, act to slow up the rate of retrogradation, but the process is inevitable and will occur quickly if the bread is unwrapped and exposed to air.
Hard starches, such as crackers, are crisp because they are baked with an extremely low moisture level, usually 2 to 5 percent. When they soften, their internal structure doesn’t change like staling hard breads. As they are exposed to the ambient air, crackers absorb the air’s moisture. According to Jackel, hard crackers will be perceived as soft once the moisture level reaches 9 percent.
Submitted by Robert Prots of Waverly, Ohio. Thanks also to Jim Clair of Philadelphia, Pennsylvania
.
Why
do Hardcover Books Have Exposed, Checkered Cloth as Part of Their Bindings (on Top and Bottom)?
We are ashamed, almost morose, about the fact that we have spent nearly forty years of our lives reading books and never noticed the checkered cloths until reader Valerie Y. Grollman came into our lives. After we received Ms. Grollman’s letter, we fondled many books in our collection and discovered that just about all our hardbound books did, indeed, have this embellishment on top and bottom.
We contacted several publishing authorities and received a fascinating historical explanation from Gerald W. Lange, a master printer associated with Los Angeles’s Bieler Press. His remarks were so interesting that, with his permission, we are quoting them at length:
The “cloth” you refer to is the “headband,” which was originally a cord or cloth tape with colored thread or string tightly wound around it. The headband was an integral part of the binding structure in early forms of the “codex” book. The codex has been with us for nearly two thousand years and is the physical form of the book we are all familiar with today. (The primary ancestral form of the book prior to the codex was the papyrus roll.)
In early examples of the codex, the thread winding around the cord actually pierced through into the folded “signatures” [grouping of pages] of the book’s “text block” [the finished, sewn gathering of the signatures] and the cord itself was tied to the edges of the binding’s casing at the head (upper) and tail (lower) of the spine, and as such, provided a great deal of structural strength to the binding.
Some historians have suggested that a later and more cosmetic function of the headband was to hide from view the internal casing material of the binding’s spine. Early Western books were part and parcel of a pervasive religious world view and any visually displeasing structural imperfections were hidden or disguised with decoration. Long after original intent, of course, traditional practices remain in place.
With the development of commercial bookbinding production during the Industrial Revolution, the headband became less structurally important and was merely attached to the edges of the text block, rather than sewn into it. Today the headband serves a purely decorative purpose, and is now more often a thin strip of colored or patterned cloth glued to the edge of the spine. There are still a few fine craft hand binders who will take the time to provide headbands in the “old fashioned” way.
Lange mentions that a second theory has been advanced to explain the origins of the headband: It might have served as a buffer to support the spine material “at its vulnerable edges.” We tend to pull books from a shelf by yanking on the top of the spine and pulling the spine backwards, which places obvious stress upon the cover. Lange dismisses this theory as the original reason for the headband, since the codex book, for more than one thousand years of its existence, was designed to lie flat, not upright. Bookshelves didn’t exist, and most books were too heavy and cumbersome to stand upright.
Stephen P. Snyder, executive vice-president of the Book Manufacturers Institute, concurs with Lange’s historical assessment and adds that headbands have sometimes served the purpose of hiding glue that has seeped out of the adhesive bindings of books. When the headband is applied mechanically, as they are in most commercial books today, the bands are fed from a big spool. With the spiraling cost of hardcovers, it is nice to know that one step on the assembly line is there merely to apply some thread to make your book a little prettier.
Submitted by Valerie Y. Grollman of North Brunswick, New Jersey
.