In Packing the Ice into the ice chamber, attention is required to prevent any dirt from adhering to the ice and being packed into the ice chamber, where it will accumulate in the drains and on the floors as the ice melts.
At S, in [Fig. 68], will be found an opening over the drip pan; through these openings, placed at convenience along the back of the floor, the floor can be flushed with water and washed clean.
Time, labor and convenience are all conserved by the use of such necessary tools as are listed on previous pages. More can be added as the amount of ice cut is increased.
The Ice Field should be kept free from snow by scraping from time to time. For clearing the small surface from which a harvest of forty tons can be secured, a simple scraper, cheaper than those used on large fields, will answer the purpose. An oak plank one and one-half inches thick, ten inches wide and six feet long, with two holes four inches from the bottom edge, and four feet apart, and a foot board mortised through the center, will do tolerable work. An iron shoe on the lower edge adds materially to its efficiency. [Fig. 80] illustrates a scraper of this pattern.
Thirty-six cubic feet of ice weigh a ton. Hence, a surface six feet square on an ice field, where the ice is a foot thick, represent a ton of ice. At this rate a surface thirty-eight feet square would represent forty tons of ice. Owing to loss by breakage, and irregular cutting, it is usual to allow a considerable margin, greater in small than in large quantities, and a surface fifty feet square would readily harvest forty tons of twelve-inch ice. Where the ice is thinner a correspondingly larger surface is required to secure the same weight of ice.
The surface being cleared of snow, the ice plow is set upon the ice alongside a line drawn taut in the direction in which the plowing is to be done. The ice plow, drawn by hand and guided to run parallel with the line, gives the base groove. The blade of the guide is placed in this groove, and the field is now grooved in uniform spaces in one direction. The plow makes only one cut in each groove, while the guide is attached to it. By repeating this method grooves are made crossing those first made at right angles. The guide is now removed from the plow, and by plowing back and forth the ice is grooved to the depth desired, about seven or eight inches for twelve-inch ice and two inches for six-inch ice.
A channel is now opened at the foot of the incline, and a few hours work for four men, and a boy driving the horse to run the grapple, will land the ice cakes on the platform.
CHAPTER VII.
Artificial Ice and Cold Air Machines.
Historical Sketch—The First Ice Machine—Its Subsequent Development—Progress in the Use of Machines—The Principles Involved in their Construction—Diversity of Application—Recent Discoveries.