Do Penguins Have Knees? by David Feldman

more] to build displays, cart trash, and carry stuff home. Why not? It didn’t cost them anything.
     Now, however, the New York State law requires that markets must account for all cases to their milk suppliers. They are required by law to pay $2.00 for every case unaccounted for. Consequently, there is now much stricter control over the cases.
     As a final note, it was discovered by some city milk dealers that shipments of new cases were being stolen, sent to plastic recyclers for some amount of money, to reappear as any one of a vast multitude of plastic gewgaws. All in all, it was a very big rathole through which a big piece of milk-generated money (ultimately from consumers) was being lost. The law has not eliminated all theft, but it has sharply reduced the problem.
     
    The great irony, of course, is that the milk carton laws turn the tables on retailers. Supermarkets, often so reluctant to process recycled bottles and cans, now must do the same thing themselves, further proof that recycling efforts seem to work only when strong financial incentives exist.
     
    Submitted by Mitch Hubbard of Rancho Palos Verdes, California. Thanks also to Gregory Reis of Torrance, California .
     
     
    Why Does Shampoo Lather So Much Better on the Second Application?
     
    Even if our hands and hair are already wet, we can’t seem to get a healthy lather on the first try when we shampoo our hair. But after we rinse, the shampoo foams up like crazy. Why is lather more luxuriant the second time around?
    Evidently, it’s because we have greasy hair, according to Dr. John E. Corbett, vice-president of technology at Clairol:
     
         In the first shampoo application, the lather is suppressed by the oils in the hair. When the oils are rinsed off [by the first application], the shampoo lathers much better on the second application.

Submitted by Joe Schwartz of Troy, New York .
     
     
    Why Don’t Cigarette Butts Burn? Is There a Particular Barrier Between the Tobacco and the Filter That Prevents the Burn?
     
    Even cigarettes without filters don’t burn quickly. If the shredded tobacco is packed tightly enough, not enough oxygen is available to feed the combustion process. The degree of porosity of the paper surrounding the tobacco rod can also regulate the degree of burn.
    On a filter cigarette, however, an extra impediment is placed on the combustion process; luckily, it is not asbestos. Mary Ann Usrey, of R. J. Reynolds, explains:
     
         The filter is attached to the tobacco rod by a special “tipping” paper which is essentially non-porous. This paper acts to extinguish the burning coal by significantly reducing the available oxygen. So, in effect, there is a barrier between the tobacco and the filter, but it is around the cigarette, not actually between the tobacco and the filter in the interior of the cigarette.

Submitted by Frank H. Anderson of Prince George, Virginia .
     
     

     
     
    What Are You Hearing When You Shake a Light Bulb?
     
    Would you believe the ocean? We didn’t think so.
    Actually, what you are hearing depends upon whether you are shaking a functional or a burned-out bulb. If you are shaking a newish, functioning bulb, chances are you are hearing the delightful sound of loose tungsten particles left over in the bulb’s glass envelope during its manufacturing process.
    According to Peter Wulff, editor of Home Lighting & Accessories , these loose particles don’t affect the bulb’s operation or lifespan. Wulff adds that although the tungsten particles aren’t left in the bulb deliberately, at one time manufacturers of high-wattage tungsten halogen bulbs did leave such residue: “Occasionally, it was recommended that after use and after the bulb cooled, the bulb should be turned upside down and then shaken to allow the loose particles to clean the inside of the glass.”
    But today if you hear something jangling around, chances are that you are shaking a burned-out bulb. In