The heads of needle grass detach from the stalks and have the barbed design of arrows.
It is not clear whether differences in efficacy exist between laser and needle acupuncture given that there are no direct head-to-head comparisons of needle and laser acupuncture for chronic knee pain., However, in a systematic review, laser but not needle acupuncture offered statistically and clinically significant short-term pain relief over placebo [ 11].
Whenever hand-sewing instructions direct you to push a needle through fabric, make sure that you are wearing a thimble to prevent needle pricks that may occur as you exert a force against the head of a needle that is strong enough to force the needle through fabric.
Standard procedure for CSF collection by lumbar puncture [ 13] (However, it should be noted that touching any part other than the plastic head of the needle may raise sterilisation issues) involves the fluid being passed typically through a 20- to 22-gauge spinal needle (sometimes with a catheter) and dripped into a collection tube.
Of course, the theory of evolution by natural selection would have been true even if it had been scratched in Morse code on the head of a needle.
The amount of flesh removed, if any, was alternately described by circumcisers as being the size of a quarter-grain of rice, a guava seed, a bean, the tip of a leaf, the head of a needle.
Lovelock, who trained as a chemist but is just as interested in and likely to expound upon physics and biology, detests academic compartmentalisation. "The universities," he says, "have reached a point similar to the monasteries in the middle ages where the monks counted the number of angels that could stand on the head of a needle".
And then, when you look through a magnifying glass and see a painted sculpture of Disney's Goofy standing on the head of a needle, or learn how the stage machinery of Baroque theaters created the illusion of flowing water, or are told that some South American bats seem to fly through solid objects, you won't have the same mixture of shock, marvel, delight and confusion as I did.
