738. _To manage a Watch._--_First_: Wind your watch as nearly as possible at the same hour every day. _Secondly_: Be careful that your key is in good condition, as there is much danger of injuring the machine when the key is worn or cracked; there are more mainsprings and chains broken through a jerk in winding, than from any other cause, which injury will, sooner or later, be the result, if the key be in bad order. _Thirdly_: As all metals contract by cold, and expand by heat, it must be manifest, that to keep the watch as nearly as possible at one temperature, is a necessary piece of attention. _Fourthly_: Keep the watch as constantly as possible in one position--that is, if it hangs by day, let it hang by night against something soft. _Fifthly_: the hands of a pocket-chronometer or duplex watch, should never be set backwards; in other watches this is a matter of no consequence. _Sixthly_: The glass should never be opened in watches that set and regulate at the back. One or two other directions more, it is of vital importance that you bear in mind. On regulating a watch, should it be fast, move the regulator a trifle towards the slow, and if going slow, do the reverse; you cannot move the regulator too slightly or too gently at a time, and the only inconvenience that can arise is, that you may have to perform the duty more than once. On the contrary, if you move the regulator too much at a time you will be as far, if not farther than ever, from attaining your object; so that you may repeat the movement until quite tired and disappointed--stoutly blaming both watch and watch-maker, while the fault is entirely your own. Again, you cannot be too careful in respect of the nature and condition of your watch-pocket; see that it be made of some material that is soft and pliant--such as wash-leather, which is the best; and, also, that there be no flue or nap that may be torn off when taking the watch out of the pocket. Cleanliness, too, is as needful here as in the key before winding; for if there be dust or dirt in either instance, it will, you may rely upon it, work its way into the watch, as well as wear away the engine turning of the case. PART IV. DOMESTIC ECONOMY, AND OTHER MATTERS WORTH KNOWING. _Of the different kinds of Tea, Coffee, &c.--Preserving Fruits, Flowers, &c.--Care of Fires--and other Hints._ TEAS. 739.--The names of the different kinds of tea, relate to the time of their being gathered, or to some peculiarity in their manufacture. It is a general rule, that all tea is fine in proportion to the tenderness and immaturity of the leaves. The quality and value of the different kinds diminish as they are gathered later in the season. BLACK TEAS.--As soon as the leaf-bud begins to expand, it is gathered to make _Pekoe_. A few days' later growth produces black-leaved Pekoe. The next picking is called _Souchong_; as the leaves grow larger and more mature, they form _Congou_; and the last picking is _Bohea_.