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MECHANICAL. 



will be good drainage. The pen may be 

 made of rails twelve feet long, or of any 

 desired length. The larger the pen, the 

 better the ice will keep. Lay up two 

 rails upon each of the four sides. Make 

 the botton level, and cover it a foot or 

 •more with straw, sea-weed, or any con- 

 venient refuse vegetable matter. Sawdust 

 is better than straw, if it can be had. 

 Spent tan-bark is a good material for this 

 foundation. Cut the cakes of ice in the 

 usual manner, and pack them closely, 

 filling the interstices with pounded ice, 

 and if the weather is freezing pour on a 

 little water to make it solid. Pack the 

 outside with a foot of straw, sawdust, or 

 other material, and put up the fence as 

 the pile of ice rises. The pile can be 

 -conveniently made about eight feet high. 

 Cover the top with at least eighteen 

 inches of sawdust, or two feet of straw 

 trodden down closely. Make a roof of 

 boards or slabs slanting to the north, 

 sufficiently steep to shed water, and fasten 

 with a few nails. Such a pile of ice as 

 this can be secured by a couple of men 

 and a team in a day. A cheap ice-box 

 made with double sides and packed with 

 sawdust will be wanted. The inner 

 chamber should be about two feet long, 

 two feet deep, and eighteen inches wide. 

 This will hold a single cake of ice weigh- 

 ing a hundred pounds or more, and leave 

 room on top to keep milk, fresh meats, 

 fruit, and other matters. It will last from 

 four days to a week, according to the 

 quantity that is used in the drinking- 

 water. If the extemporaneous ice-house 

 is not disturbed more than once a week, 

 it will probably supply the family through 

 the summer with abundance of ice. 



LIGHTNING BODS, How to Erect.— 

 i. The rod should consist of round iron 

 of about one inch in diameter ; its parts, 

 throughout its whole length, should be in 

 perfect metallic continuity, by being se- 

 cured together by coupling ferrules. 2. 

 To secure it from rust the rod should be 

 •coated with black paint, itself a good 

 conductor. 3. It should terminate in a 

 single platinum point. 4. The shorter 

 and more direct the course of the rod to 

 the earth the better ; bcndings should be 

 rounded, and not formed in acute angles. 

 3. It should be fastened to the building 

 by iron eyes, and may be insulated from 

 those by cylinders of glass (We do not, 



however, consider the latter of much im- 

 portance.) 6. The rod should be con- 

 nected with the earth in the most perfect 

 manner possible, and nothing is better 

 for this purpose than to place it in metal- 

 lic contact with the gas-pipes, or, better, 

 the water-pipes of the city. This con- 

 nection may be made by a ribbon of 

 copper or iron soldered to the end of the 

 rod at one of its extremities, and wrapped 

 around the pipe at the other. If a con- 

 nection of this kind is impracticable, the 

 rod should be continued horizontally to 

 the nearest well, and then turned verti- 

 cally downward until the end enters the 

 water as deep as its lowest level. The 

 horizontal part of the rod may be buried 

 in a stratum of powdered charcoal and 

 ashes. The rod should be placed, in 

 preference, on the west side of the build- 

 ing. A rod of this kind may be put up 

 by an ordinary blacksmith. The rod in 

 question is in accordance with our latest 

 knowledge of all the facts of electricity. 

 Attempted improvements on it are worth- 

 less, and, as a general thing, are proposed 

 by those who are but slightly acquainted 

 with the subject. 



MEASUREMENT OF SLATERS' AND 

 TILERS' WORK.— In these articles, the 

 contents of a roof are found by multiply- 

 ing the length of the ridge by the girts 

 over from eaves to eaves; making 

 allowance in this girt for the double 

 row of slates at the bottom, or, for how 

 much one row of slates or tiles is laid 

 over one another. When the roof is of 

 a true pitch — that is, forming a right an- 

 gle at the top, then the breadth of the 

 building, with its half added, is the girt 

 over both sides, nearly. In angles formed 

 in a roof, running from the edge to the 

 eaves, when the angle bends inward, it is 

 called a valley ; but when outward, it is 

 called a hip. Deductions are made for 

 chimney shafts or window holes. 



MEASUREMENT, GLAZIERS' WORK 

 — Glaziers take their dimensions either in 

 feet, inches and parts, or feet, tenths and 

 hundredth, and they complete their work 

 in square feet. In taking the length and 

 breadth of a window, the cross bars 

 between the squares are included. Also 

 windows of round or oval forms "^e 

 measured as squares ; measuring them v 

 their greatest length and breadth, on ac- 

 count of the waste in cutting the glass. 



