Surely those produce a touch of reverberance?

Furthermore, a good light incoupler is also a good light outcoupler and therefore it is important to prevent the incoupled light from hitting back to the grating structure.

Sir, as I said last time, labour to keep your alacrity and dignity, in an even temper: for in a dark sadness, indifferent things seem abominable, or necessary, being neither; as trees, and sheep, to melancholy night-walkers, have unproper shapes.

Physical methods are sometimes used to reduce or eliminate fertility. Methods include physical addling and surgical sterilization. Meaning loss of development, addling in the strictest sense is destruction of eggs by shaking. Addling has come to mean destroying eggs by any physical or chemical means – puncturing, freezing, or coating with vegetable oil.