To one peck of freshly slaked lime add half an ounce of carbolic acid. Mix very thoroughly, and add same quantity, in bulk, of tobacco dust. Another powder recommended by Dr. Woods in the same article, and which I have used very frequently, is made by mixing equal parts of finely-sifted coal ashes and tobacco dust, then moisten the whole with the liquid louse exterminator. Allow it to dry and it is ready for use. When purchasing carbolic acid, ask for ninety per cent. strength, otherwise they are very likely to give you a much weaker preparation, fit only for medical use.
THE SITTING HEN AND THE INCUBATOR
Looking back over the memories of my farm initiation, it seems as if I had not fully realised the possibilities of my new undertaking until the first incubator was inaugurated. As I have already told you, I did all the first year’s hatch under hens, and still set every hen that evinces any desire to assume the cares of motherhood, because it seems Nature’s plan to keep the egg machine in good working order. If a broody hen is not allowed to sit, it takes several days of incarceration to break up her desire, then several days more after she is freed before she commences to lay, and invariably the sitting fever will attack her again within a few weeks. Now, incubation takes only three weeks; brooding of chicks, another four or six weeks, and Mrs. Biddy has had a complete rest, followed by vigorous exercise while scratching for her babies. So when she is returned to the yard she is in perfect condition to produce eggs. Let Biddy sit whenever she wants to, but don’t wait her pleasure in the early spring, for you might have no young chickens to sell when they bring good prices.
THE SELECTION OF THE INCUBATOR
There are a great many incubators on the market, some heated by hot air, others by hot water. If you select any one of the standard makes advertised you will get a good, practical hatcher. Printed instructions for setting up and running are sent out with every machine, but they don’t emphasise all the important points quite strongly enough for amateurs. Lots of people can’t drive a screw home accurately, and fail to realise that if the head is slightly to the right or left it throws the fixture which is being attached to the machine out of plumb, and a hair’s breadth makes a difference when such delicate appliances as thermostatic rods (the power which controls the heat), are concerned. A blunder supplies much knowledge. I should never have realised the necessity for absolute exactness if one of the screws used in attaching the lamp support to our second incubator had not gone slightly awry. It caused the chimney almost to touch one side of the socket into which it fits. That, in turn, drew the flame to one side, and caused it to smoke at night when turned up for extra heat. It was a very little blunder, apparently, but it almost spoiled the incubator, and quite spoiled the hatch.
To be sure that the incubator fixtures are plumb, use a spirit level, the only safe guide. After starting the machine, practise running it for a few days before putting in the eggs. When the heat reaches one hundred and two and one-half degrees, with the escape dial hanging the width of a match from the opening, put in the trays, which, being cold, will lower the heat, and should close the dial until the trays become warm, and the thermometer in the machine again registers one hundred and two and one-half, when the dial should once more be dangling the match width above the opening. Should the closing and opening not take place as the heat varies, the machine is not properly adjusted, and you must practise until it will bear the test before putting in the eggs.
The thermometers are supposed to have been tested before they are shipped, but it is well to buy an extra one and compare them; or get your doctor, who is sure to have an accurate thermometer, to do it for you. The egg tester comes with the incubator. It is a tin, funnel-like chimney that fits over the lamp, and has a projecting opening, bordered with black, before which to hold the eggs. The first test should be made on the seventh day; the second on the fifteenth day. Hold the egg, large end uppermost, in front of the opening. If it looks perfectly clear it is infertile and can be used to feed young chicks. If it shows a dark-red spot with spidery legs it is fertile, and must be returned to the incubator. Dead germs are rarely discernible at the first testing, except to the expert eye. By the fifteenth, the veriest amateur will be able to detect them.
Successful incubation depends principally on being able to maintain the amount of heat and moisture necessary at the different stages of development. A thermometer is furnished with most incubators, but as yet hygrometers are not, so it is advisable to buy one. For as they only cost $1.50 each, it would be pennywise and pound-foolish to do without one. Having these two little instruments to tell exactly the amount of heat and moisture present in the machine, simplifies the work wonderfully.
Personally, I like to have the thermometer register 102 degrees, and the hygrometer 75, when I first put the eggs in the incubator. The second week, the heat is increased to 102½, and the moisture lowered to 70 degrees. The third week, heat from 102½ to 103; moisture not over 45 until the nineteenth day, when the moisture is again increased to 55 or 60 degrees.