. The poultry manual. A complete guide for the breeder and exhibitor . of Spratfs Patent, Limited, whoare the proprietors. This was patented in 1881, andto-day there are probably more in use than of anyother make. For some 20 years it stood practicallyalone. But after the patent expired a host of com-petitors sprang up. Some few have approached it forefficiency, and may be obtained at a less cost, but nonehave excelled it, so far as my experience goes, and veryfew are at all fit to be compared with it. I have hadone of Hearsons machines working for 19 years, aperiod of six months each year, an
. The poultry manual. A complete guide for the breeder and exhibitor . of Spratfs Patent, Limited, whoare the proprietors. This was patented in 1881, andto-day there are probably more in use than of anyother make. For some 20 years it stood practicallyalone. But after the patent expired a host of com-petitors sprang up. Some few have approached it forefficiency, and may be obtained at a less cost, but nonehave excelled it, so far as my experience goes, and veryfew are at all fit to be compared with it. I have hadone of Hearsons machines working for 19 years, aperiod of six months each year, and it is in nearly as INCUBATION 61 good a condition now as when I bought it. The cap-sule, which was the main secret of the patent, is still atwork, and has never wanted attention. In no otherincubator that I know of is it safe to work withouthaving a spare capsule at hand in case the one at workshould fail. -■ This capsule, which is seen in position in the sectionof Hearsons Incubator below, consists of two copperplates superimposed and hermetically sealed at the. Fig. S. edges. Within the two plates are a few drops of aliquid composed of ether and alcohol, etc., which boiland expand at a temperature of 98°, just as water boilsat 212°. When the capsule expands it raises the leverwhich rests upon it, and this lifts the damper over thelamp-flue and lets off all excess of heat. There is noother capsule so delicately adjusted or so strongly mechanism of Hearsons Incubator will be readilymiderstood from the sectional view shown above A A is the tank of water^ filled at tube R. B B—Movable egg-tray. C C—Movable water-tray covered with perforated galvanized 62 THE POULTRY MANUAL cover and canvas cloth to allow absorption of moisture and airwithout draught. D D—Holes in the bottom and false bottom for admission offresh air^ the arrows showing its course. E E—Holes for admission and exit of fresh air in back andfront of incubator. F—Damper over flue V^ Avhich lif
Size: 1913px × 1306px
Photo credit: © Reading Room 2020 / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1910, bookidpoultr, booksubjectpoultry
