File:Du Pont farmer's handbook; instructions in the use of dynamite for clearing land, planting and cultivating trees, drainage, ditching and subsoiling (1911) (14595943777).jpg

Identifier: dupontfarmershan00eidu (find matches)
Title: Du Pont farmer's handbook; instructions in the use of dynamite for clearing land, planting and cultivating trees, drainage, ditching and subsoiling
Year: 1911 (1910s)
Authors: E.I. Du Pont de Nemours, Powder Co., Wilmington, Del
Subjects: Explosives
Publisher: Wilmington, Del., E.I. du Pont de Nemours Powder Co.
Contributing Library: The Library of Congress
Digitizing Sponsor: Sloan Foundation

View Book Page: Book Viewer
About This Book: Catalog Entry
View All Images: All Images From Book
Click here to view book online to see this illustration in context in a browseable online version of this book.

Text Appearing Before Image:
f these should be charged witha half of a 11/4 x 8-inch cartridge of Red Cross 25% Extra Dyna-mite primed with blasting cap and fuse. The holes should then befilled compactly with tamping to the surface. Holes may be putdown either with the subsoil bar or with a dirt auger. The ex-plosion of the charge should not affect the surface mucli because mostof the force of the dynamite is given to breaking and shattering thesubsoil from seven to ten feet around the hole. When blasting hardpan the holes should be bored to withinabout SIX inches of the bottom of the hardpan and the charge of dyna-mite placed at that point, the object being to shatter the greatest areapossible and not to merely make a chamber in the ground underneathit. The spacing of holes and kind of dynamite should be approxi-mately the same as when blasting ordinary subsoil. In some places,however, where the hardpan is unusually thick and deep, it is neces-sary to use two-thirds of a cartridge or a whole one in each hole. 58
Text Appearing After Image:
TREE PLANTING AND CULTIVATING In some kinds of hardpan, like cemented gravel, it may be neces-sary to vary a little the instructions given above. These instructionswill, how^ever, answer for a guide until practice shows that someslight changes in the way of blasting these irregular hardpans willbe of advantage. If properly done it may not be necessary to blastsubsoil or hardpan more often than once in ten years. The results are better if subsoil blasting is done when the ground is fairly dry because wet subsoil is not so easily cracked and shattered as that which is dryer. Table Showing the Approximate Number of Pounds of Dynamite Requiredand the Approximate Cost, Including Explosives, Blasting Supplies and Labor, toBlast an Acre of Subsoil or Hardpan. Distance BetweenHoles Each Way No. of P4x8 Cartridges of Red Cross23 ,c Extra Dynamite . Ml Approximate CostApproximate TJumber \ \ v r\ , „ \ t y-\ Including Dynamite,ol rounds ol Uyna- me i . Lslasting buppliesmite per Acre , , , an

Note About Images