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Full text of "Hand book of explosives; instructions in the use of explosives for clearing land, planting and cultivating trees, drainage, ditching, subsoiling and other purposes"

Hand Book 

of 

Explosives 



Instructions in the Use of Explosives 
for 

Clearing Land, Planting and Cultivating 

Trees, Drainage, Ditching, 

Subsoiling and other 

Purposes 



L 



E. I. du Pont de Nemours & Company 

Eatablished 1802 

Wilmington, Delaware 



(May. 1917) 



Cornell University Library 
S 679.D93 1917 
Hand book of explosives; inst^ruc^^^^^ 




3 1924 003 353 848 



ME 

Hand Book of Explosives 



Instructions in the Use of Explosives 
for 

Clearing Land, Planting and Cultivating 

Trees, Drainage, Ditching, 

Subsoiling and other 

Purposes 



E. I. du Pont de Nemours & Company 

Established 1802 

Wilmington, Delaware 



Copyright 1917 

E. 1. du Pont de Nemours & Company 

Wilmington. Del. 



Inde: 



PAGE 

An Under-Sized Farm 5,6 

Amount of Dynamite Required for a Given Length of Ditch 86 

Big Tree Stump Blasting 40-42 

Blasting Caps — Du Pont 15 

Blasting Caps — Du Pont Electric 16, 17 

Blasting— Electric 32, 33 

Blasting in Orchards — Tree Planting 66-76 

Blasting Machines — Du Pont, 17, 18 

Blasting — General Directions 23-33 

Blasting Supplies 15-19 

Blockholing Boulders 53, 54 

Bore Holes — Mating in Hard Ground 22 

Boulder Blasting — Charges and Methods 53-56 

Cap Crimpers 16 

Caps — Du Pont Blasting 15 

Cellar Excavating 97, 98 

Clearing Land 34-56 

Detonation 23 

Digging Ice and Fish Ponds 103, 104 

Ditch Blasting— Restdts of 81, 82, 89 

Ditch Blasting With Blasting Machine 86-90 

Ditches — Cross Section of Blasted 87 

Ditches— Methods of Digging 78, 79 

Ditching Charges 85, 86, 90 

Ditching Costs 79-81 

Ditching Diagrams 85, 87-90 

Ditching Instructions 78-90 

Ditching— Without Blasting Machine— Test Shots 83-86 

Ditch Wiring 88 

Drainage — Charges for Vertical 95 

Drainage— Vertical 60, 92-95 

Draining Ponds and Swamps 92-95 

Dynamite — Handling, Hauling, Storing and Transportation, etc. . . 8-14 

Electric Blasting 32, 33 

Electric Blasting Caps ■ 16, 17 

Erosion — Blasting for the Control of 63-65 

Explosives for Farm Use 8-17 

Explosives for Ditching and Drainage 87 

Explosives Recommended for Tree Planting 73 

Firing Charges 30 

Foundation Excavating 97, 98 

Fuse 15, 16 

Galvanometer — Use of 19 

Gully FUling 64, 65 

Ice Blasting '. 99-101 



Index — Continued 

PAGE 

Kinds of High Explosives 10, 1 1 

Land Clearing — Combination Methods 44-47 

Land Drainage 77-95 

Lateral-Rooted Stumps, Blasting 38, 39 

Lime 62 

Loading 28, 29 

Log Jams — Starting 101, 102 

Man Power — Saving 7, 34 

Methods of Connecting Wires for Electric Ditch Blasting 88 

Misfires 31; 32 

Mudcapping Boulders 54, 55 

Piling Stumps 47-50 

Planting Trees '. 66-76 

Pond Drainage 92-95 

Posthole Blasting 104-107 

Priming Cartridges 23-27 

Propagated Ditch Blasting .83-86 

Rejuvenating Old Fruit Trees, Shade Trees, Vines and Bush 

Fruits 75, 76 

Rheostat — Use of 19 

Road Building 98, 99 

Scrapping Old Machinery 102, 103 

Seam Blasting 55 

Setting Trees 72, 73 

Shooting Wells to Increase Flow of Water 96, 97 

Snakeholing Boulders 54 

Stream Correction 90-92 

Stump Blasting 35-52 

Stiimp Blasting — Hollow 40 

Stump Blasting — Table of Charges 43 

Stump Blasting — ^West Coast 40-42 

Subsoil — Breaking Up — Different Types of Hardpan 57-65 

Table of Charges for Electric Ditch Blasting. 90 

Tamping Bore Holes '. 29, 30 

Tap-Rooted Stumps — Blasting 35-37 

Thawing Dynamite 12-14 

Tile Draining — Blasting to Increase Action of 61 

Tools for- Agricultural Blasting 20-22 

Tree Felling 44 

Turpentine Industry — Use of Explosives in the 51, 52 

Vertical Farming ■ 57-65 

Well Sinking 95-97 

Wire — Connecting 19 

Wire — Leading 19 



The Under-Sized Farm 

Every possible acre of the farm should be used to its maximum 
capacity. The few acres of waste land on one farm is a personal 
matter that deserves the immediate attention of the individual fanner. 
The total aggregate of these spots is enormous and of the most serious 
concern to the nation. 

The causes of waste land usually are : stumps, boulders, wet spots, 
gullies and hardpan. The two accompanying sketches are to show how 
one or all of these troubles may reduce the workable size of the farm, 
and the farm after being made full size. 

Stumps cause "Loafer Land" by taking up space in the fields, by 
prohibiting economical cultivation, by making breeding places for weeds 
and crop pests, and make the farm unsightly. Our sketch shows them 
encumbering the most fertile field on the farm, and preventing the 
bringing of the back pasture into the much needed rotation. 

Boulders offer the same general troubles as stumps and are shown 
assisting the stumps in dwarfing our farm. 

The overflow caused by the shallow, crooked stream channel takes 
away more good land and replaces it with a swamp that breeds disease 
and does not even afford g-ood pasture. The spring and its shallow 
outlet make this condition still worse. 

A part of the back fields are gullied and cut up into small patches 
that cannot be handled successfully. The fertile surface has been 
washed away. The bald or galled spots will not produce because there 
can be no storage of moisture and no humus. 

The tight clay cuts off the under side of the farm and is always 
effective in reducing the productive size of the f ajni by .taking from 
it the third dimension — depth. It reduces yields of field crops and kills 
or stunts the trees. 




I.AJ=iG£ FERTILE CULTIVATED 
FIELD TROUBLED WITH '^ 

BOULDERS AND OLD STUMPS 
6 



# 



WELL CLEARED 
CULTIVATED F/ELD 
TROUBLEO- WITH 
TIGHT CLAY 
SUBSOIL 



LOW tt WET 



fftUITS 




© © c© ® @ ® 

®©^®«&® 

OLD ORCHARD W 
BAD SHAPE. OU 
ACCOUIVT OF 
HARDPAN 



THE UNDER-SIZED FARM SHOWING HOW THE PRODUCTIVE AREA IS 
REDUCED BY DEFECTS THAT BLASTING WILL CORRECT 



Our farm looks bad. It is not full sized, being only one-third 
efficient in crop production. It is typical in one feature or another ot 
practically every farm. 

The desire is for the use of all the land, large fields, good crops, a 
good orchard, a bounteous garden and an attractive house. 

In changing this abject proposition to a full-sized farm we natur- 
ally want to begin on the easiest places. 

The otherwise good bottom has but to be rid of stumps to make :t 
conform to the highest ideals of the owner. These stumps are old and 
dead, and but small charges of explosives are required to dispose of 

them. ■ r 

The gullies and bare spots in the big field follow next, as a Ime ot 
lightly loaded charges will tumble the gullies so near full of soil that 
they can be plowed across and brought into actual cultivation. Sub- 
soil shattering and a coating of manure will revive the bald spots and 
the rest of the hardpan and the field is all ready for the green manure 
crop to fit it for a fruitful orchard and good staple crops. 

With these two big Aelds in good condition attention is turned to 
drainage and the water from the wet spot back of the house disappears 
through crevices blasted into the underlying ground. A blast from a 
long line of loaded holes makes a fine straight channel for the creek 
and a line of lighter loads lowers the spring branch so that all of the 
fertile swamp becomes field or meadow. 

Spare hours spent in blasting the yard, garden and old orchard 
enlivens flowers, trees and vegetables, and lays the foundation for 
future good years for each of them. 

When all else is done the rough old pasture can be attacked as 
occasion affords. When the stumps and boulders are all gone the once 
unsightly spot can be brought into the regular rotation. 




^ ROUGH PASTURE BEING SLOWLY^^ 
CLEARED OAT ODD TIMES TO 
MAKE CUITNATEO' FIELD 

•^O^ERtllTQF ^ 
, ROTATION ^ 

'"'""^ BETTER GRAZI' 
MEANTJriE^ 

,^ .„, 

■BRANCH RUN 




STREAM 
DEEPENED & 

STRAIGHTENS^/ GULLIES F/LLEO. 
BALD SPOT GONE, 
SUB50IL SHATTERED, 
EROSION STOPPED. 
LAR&E FIELD, GOOD YIELDS 



ORCHARD SITE 
GULLY FILLED 
UP, TREE HOLEl 
BLASTED, 
EROSION 
STOPPED. 
FINE CONDITIO^ 



RICH BOTTOn l-AND 
CLEARED OF STUnPS AND 
BOULDERS AND EA^Y TO TILL 



HARD PAN 
SHATTERED 



GARDEN 
SUBSOILED 
And 
mPROVED 



i© ® 






YARO TREES AND (S lShih&iWi& 
SHRUBS REJUVENATBOy. ISFlfei^^Tn 

©(©©(§ ®@ 
^NET-SROT g^^ ORCHARD 

DRAINED BY REJUVENATED 

BLAST 



THE FULL-SIZED FARM, GIVING THE ENTIRE AREA OF PRODUCTIVE 
LAND AFTER IT HAS BEEN IMPROVED WITH EXPLOSIVES 



Saving Man Power 

Lands have been cleared, drained and tilled for many years by ' 
the prodigal use of labor or Man Power. 

Larger areas are yet to be cleared and further improvements must 
be made in millions of other acres in order to supply the ever-increasing 
demand for food and clothing. 

Man is too intelligent and valuable in other ways to have his efforts 
and energy entirely consumed by the heavy forms of brute drudgery 
that can better be done by the employment of modern labor savers. 

His knowledge, intelligence and energy are much more valuable to 
himself, the community and the country at large, when employed in 
directing the forces which have been placed at his disposal by nature 
and science. 

The work must be done better than ever before, as the modern 
horse and power-drawn farm equipment cannot be used to advantage 
save on well-cleared lands. 

Old methods of developing land by Man Power alone can be used 
no longer, for the greatest scarcity, at present, is labor. 

It is indeed so scarce and, when available, so expensive, that it 
is becoming increasingly difficult to make developments or to install 
labor-saving devices in order to effect a saving in the future. 

In many cases there seems no escape from the condition; but in 
developing lands, explosives, the modern conservers of Man Power, fill 
the needs and prove most efficient in doing the classes of work described 
in this book. 

No matter how difficult it may be to get men, explosives are always 
available and the demand for increased amounts can be quickly supplied 
for, the job. 

A saving in Man Power is a saving in money. Explosives are now 
included with horses, steam and gasoline as conservers of manual 
effort. 



Explosives for Farm Use 

Explosives are solids or liquids which can be changed instan- 
taneously by a spark, great heat or powerful shock into gases having 
many times the volume of the explosives in their original form. Coal 
and wood are changed slowly into large volumes of gas by burning; 
water is changed into a large volume of gas (steam) by heating. This 
is the whole theory of explosives ; and much in their use, which would 
otherwise seem difficult to explain, is easily understood if this be borne 
in mind. 

Blasting explosives are divided into two classes: "High Explo- 
sives" and "Low Explosives." High Explosives, more commonly known 
as "dynamite," include all of the explosives which can be properly fired 
or detonated only by means of an intermediate agent 
such as a blasting cap or electric blasting cap and not 
by simple ignition. Blasting powders are classified 
as low explosives and are exploded by a spark. 



BLASTING POWDER 

Blasting Powder is produced in granulations or 
grains of various sizes. It is packed in bulk in steel 
kegs containing twenty-five pounds. Although it 
is invaluable for many kinds of coal mining, quarry- 
ing and general excavating, it is not generally appli- 
cable to blasting about the farm except for split- 
ting logs for timber or rails. For this work blasting 
powder is fired by means of safety fuse or electric 
squibs. 




Keg of Blasting 
Powder 



DYNAMITE 

Dynamite differs from blasting powder in that it is more powerful, 
detonates with much greater rapidity, and has a greater shattering 
effect. 

The most important properties which contribute to the effect of 
dynamite are strength or disruptive power and quickness or shattering 
power. 

Other factors in the usefulness of dynamite are its stability or 
keeping qualities and qualities that tend to make it safer to handle. 
The power to resist cold and water is also highly desirable. 

These essentials can be secured and maintained only by the use of 
the highest quality of ingredients, greatest care and attention in manu- 



8 



facture, expensive and complicated machinery, skillful labor and super- 
vision, long experience, and continued tests. The Du Pont Company 
fulfills all of these requirements. It has been engaged in the manu- 
facture of explosives since 1802 and has factories in many parts of the 
United States. No other manufacturing concern in this country main- 
tains a greater number of technical chemists than are engaged at the 
Du Pont laboratories to test daily the output of the factories to prevent 
deviation from standards, and to study and experiment with explosives 
in order to improve them. Much time is spent in developing explosives 
for special classes of work. 

A corps of experts in the use of explosives is maintained, not only 
to study the exact requirements of explosives in the various fields and 
differing conditions, but to demonstrate their qualities, action and use. 

In line with our established policy to promote safety in the use of 
our explosives, the word "DANGER" is printed prominently on every 
cartridge of dynamite made by us. 

The aim is to protect all as far as possible and particularly those 
not familiar with the appearance of dynamite cartridges nor the pre- 
caution to be observed in handling them. 

The millions of pounds of our dynamites used without accident 
testify to our constant effort to assure their safety. 

Such marking, we feel, will promote careful handling because it 
will indicate to the general public as well as the regular user that there 
is an element of danger in the careless handling of cartridges of 
explosives. 

Responsible people can use and handle dynamite just as safely as 
they can handle gasoline, matches or coal oil. The energy of dyna- 
mite can be directed in the work to which it is adapted as well as 
the energy of steam can be directed in the work for which it is used. 

Dynamite is a solid closely resembling 
fine, slightly greasy sawdust, and derives its 
explosive power from different compounds 
of nitrogen. It is packed in cartridges of 
heavy, paraffin-coated paper. The standard 
size of cartridges is lj4 x 8 inches, each 
cartridge weighing approximately a half 
pound. Shipment is made in tight wooden 
cases which contain either twenty-five or 
fifty pounds (net) of dynamite. Where 
possible, users should buy by the case, as a 
better price can be obtained. 

Shipments are made in 25, SO, 75, 100, or other multiples of 25 
pound lots. 




Case of Dynamite 



KINDS OF HIGH EXPLOSIVES 

There are many different kinds of high explosives adapted to 
uses in mines and elsewhere, but for agricultural work Red Cross 
Farm Powder, Red Cross Stumping Powder, Du Pont Straight Dyna- 
mite, Red Cross Extra Dynamite and Red Cross Gelatin are the kinds 
used for various purposes, as is explained in later paragraphs. 

Red Cross Farm Powder — a slow-acting, low freezing powder 
especially adapted and manufactured for subsoil blasting, tree plant- 
ing, gully filling, loosening soils for road grading and for stump and 
boulder blasting on heavy soils. It is not recommended for stump 
blasting on sandy and other loose soils. This explosive was developed 
especially for farm use. 







CARTRIDGE OF RED CROSS FARM POWDER 

Red Cross Stumping Powder— is a stronger and quicker explo- 
sive than Red Cross Farm Powder. It is recommended for stump- 
ing, and boulder blasting on soils too light to permit the use of Red 
Cross Farm Powder, ditching with blasting machine, loosening heavy 
soil in grading, excavating cellars or foundations. It is low freezing. 

Red Cross Extra 40 Per Cent Dynamite — has the same desir- 
able features of all the Red Cross brands and is suitable for difficult 
stumping, ditching in dry soil with blasting machine, boulder blasting, 
pond drainage, ice blasting, tree felling, road grading, digging post 
holes, blasting very hard subsoils; in short, it is a general all-around 
explosive that can be used for many classes of work. The special 
brands recommended for special classes of work are advised when they 
can be conveniently obtained. It is low freezing. 

Repauno Stumping Powder and Du Pont Stumping Powder — 
are low freezing explosives manufactured to meet the stumping condi- 
tions encountered on the Pacific Coast. They should be handled the 
same as the Red Cross Explosives. They are also recommended for 
shattering hardpan and planting trees on the Pacific Coast. They are 
not sold in the East. 

Du Pont Straight 50 Per Cent. Dynamite — is quicker and 
more shattering in its action than are the Red Cross brands. Its special 
agricultural adaptation is for blasting ditches in wet soils by the prop- 
agated method (that is, without a blasting machine), for mudcapping 
hard boulders where there is a lot of the work to do, and for digging 

10 



deep post holes. It is more sensitive to shock than are the Red Cross 
brands, and requires more careful handling. It is not low freezing. 
When frozen it must be thawed. It resists water well and can be used 
in wet work. 

Red Cross Gelatin — is more plastic than the other dynamites, is 
low freezing and resists water to a marked degree. The 40 per cent, 
strength is well adapted to blasting ditches in sandy or loose material, 
and to work where charges must be under water for a long time. 

SELECT THE RIGHT GRADE 

In several cases it will be noted in the above that two or more 
explosives are recommended for the same class of work. This arises 
from the fact that practically all grades of Du Pont explosives are 
very elastic in their adaptations and can be relied on for many different 
classes of work. In selecting for a particular class of work use the 
explosive especially recommended, but where ordering small amounts 
for a number of purposes, get the one best adapted to them all. 

HANDLING, HAULING AND STORING 

Prompt Removal from Freight Station. — The law requires prompt 
removal of explosives, including blasting supplies, from freight sta- 
tions. Those expecting shipments should arrange with the freight 
agent or station master to give notification immediately on arrival of 
shipment, which must be removed within 24 hours. 

Hauling. — When transporting explosives by team always keep the 
wagon, boxes thoroughly swept. When using an open wagon protect 
the load from sparks and rain with a robe or canvas cover. Lay the 
cases of explosives flat and so that they will not shift, and never haul 
detonators and explosives together. The detonators do not weigh 
much, and can be brought along on some other trip. 

If blasting caps are purchased from a dealer, in the tin boxes sepa- 
rate from the wooden shipping case, it is a good plan to put these 
boxes in a basket or wooden box with a horse blanket, coat, hay or any- 
thing else that would keep them from being roughly jarred and shaken 
on the way home. 

Handling. — When high explosives are handled with bare hands, 
they nearly always cause headache. Cheap cotton gloves should there- 
fore be worn and destroyed before they become damp and sticky and 
clean ones provided. 

Storing. — As soon as explosives are received they should be stored 
in a dry, properly ventilated building, safe from fire and flying bullets, 

11 



and far enough away from dwellings or roads to prevent loss of life 
should they be accidentally exploded. They should be kept under lock 
and key and where children or irresponsible persons cannot get at 
them. 

If large quantities are to be stored for some time a dry, well-venti- 
lated, fire-proof and bullet-proof magazine, located in an out-of-the- 
way place should be provided. Fuse, wire, thawing kettles and blasting 
machines may be stored in the same building with the dynamite, but 
blasting caps and electric blasting caps must never be stored in the 
same building, because they are more easily exploded than dynamite. 
It would be possible to explode them accidentally by a hard shock or 
jar which would not explode dynamite. If detonators were to ex- 
plode by themselves, they would not be likely to do much damage unless 
there were a great many of them, but if they were to explode in the 
same room with dynamite, they would probably cause the dynamite 
to explode. 

Opening Cases. — When ready to use the dynamite, open the box or 
case with a hardwood wedge and a mallet. Never take more than the 
day's supply to the work, even in warm weather. In cold weather, take 
only as much as can be kept thawed until it is to be used, unless there 
are arrangements for keeping it thawed where the blasting is to be done. 

Avoid Confusion. — As soon as holes are ready for the dynamite — 
and when possible the holes should all be ready before the dynamite is 
brought to the work — the priming, charging, tamping and firing should 
be carried on as rapidly as possible without becoming careless. 

A little practice will teach the blaster to do his work quickly, sys- 
tematically and economically. 

THAWING 

Some kinds of -high explosives, such as straight dynamite, freeze 
at about 50 degrees Fahrenheit and detonate imperfectly, if at all, when 
in this condition. Even when chilled they cannot be depended on to 
work well. The different low freezing explosives described are excep- 
tions to this rule, for they will not freeze until the weather is quite cold. 
Frozen dynamite is easily recognized because it is hard and rigid. 

If, after the thawed dynamite is ready to use, something causes 
a delay and it becomes chilled or frozen before it can be put into the 
bore hole, it should be thawed again. It does not harm dynamite to 
thaw it many times, provided the work is correctly done. 

Red Cross explosives, if loaded in the ground below the frost line 
and properly tamped, will not freeze again, except in extremely cold 
weather, but high freezing explosives may chill or freeze almost imme- 
diately when loaded in cold ground, which makes it necessary to 

12 




detonate them immediately after charging. It is this power to resist cold 
that makes Red Cross explosives so valuable in cold weather. 

Dynamite can be thawed by leaving it spread out on a shelf in a 
warm room (not in a dwelling) over night, or by burying, it, while in 
the case, in green manure (see cut on page 13). It may also be thawed 
by putting it in a covered, water-tight pail and hanging this pail in 
warm water. It is exceedingly dangerous to try to thaw dynamite in 
front of an open fire, or in hot sand or ashes or on hot stones, or in an 
oven, or on hot pipes, or in hot water or steam. More accidents are 
caused by careless thawing than in any other way. 

The best way to thaw dynamite, and to keep it thawed until it is 
to be used, is in a thawing kettle made for the purpose. 

Du Pont Thawing Kettles are all made with 
a water-tight compartment for the explosives, 
which is surrounded by the receptacle for the hot 
water used to furnish the heat for thawing. This 
hot water must not come in contact with the 
dynamite. The entire kettle is made in one piece. 

While Du Pont Thawing Kettles will retain 
their heat and keep the explosive thawed for a 
considerable time, depending, of course, on the 
nature of the weather, this efifective period can 
be increased to about five times as long if the °" ^°"' Thawing Kettle 
warm kettle is kept in a barrel or box with dry hay surrounding it. 
This hay can be held in place by a cylinder of wire screen, so that the 
thawing kettle can easily be removed and replaced. If the barrel 
be mounted on two wheels with a tongue attachment, it can be readily 
drawn from point to point about the outside work, so that it will not 
l)e necessary to expose the dynamite to the cold air until it is to be 
loaded in the bore hole. Somewhat similar benefits result from wrap- 
ping old blankets or sacks around the warm kettle. 

Under no circumstances must the water be heated up in Thawing 
Kettles, even though the explosives be first removed, because nitro- 
glycerin exudes readily from warm dynamite, and enough of it is 
likely to be found in the bottom of the explosives compartment of a 
thawing kettle that has been in use for some time, to cause a serious 
accident if the thawing kettle should be placed over a fire. It is neces- 
sary to heat the water in something else before filling the water 
jacket. The hot water must always he tested before filling the dyna- 
mite compartment. If it is hot enough to burn the hand, do not put the 
explosives into tJ}e thawing kettle. Never fill the water jacket unless 
the explosives compartment is empty. See that the explosive^ com- 
partment is perfectly dry before it is filled. 

13 



Thawing kettles should be kept clean at all times. Should any 
of the explosive compounds leak out, the explosives compartment 
should be thoroughly cleaned with a solution of Sal Soda. 



TABLE OF SIZES OF THAWING KETTLES 



Du Pont No. 1 . 
Du Pont No. 2 . 



Capacity 



30 lbs. 
60 lbs. 



Weight 
Empty 



12 K lbs. 
17>^ lbs. 



Weight 
of Water 



40 lbs. 
77K lbs. 



Total Weight 
Klled 



82 >^ lbs. 
155 lbs. 



Outside 
Dimensions 



14" X U)4" 
nyi" X 21" 



The use of thawing kettles can, to a large extent, be done away 
with by using Low Freezing explosives, such as Red Cross Extra 
Dynamite and Red Cross Gelatin. 







^ '/=\.ArfVK " 



FIG 1. 



A PERMANENT MANURE THAWING BOX FOR DYNAMITE CAN 
BE EASILY BUILT ACCORDING TO THESE PLANS 



14 



Blasting Supplies 



For loading and firing charges of explosives certain accessories 
are needed. These are known as blasting supplies. 

DU PONT BLASTING CAPS 

Du Pont Blasting Caps, used for firing or detonating charges of 
High Explosives, are the big brothers of the primers in a gun shell — 
many times bigger. The No. 6 cap, which is the size recommended for 
detonating most high explosives, is a copper cylinder Ij^ inches long 
and a little less than J4 inch in diameter, closed at one end and loaded 
with 1 gram of a fulminating mixture. The No. 8 size is longer and 
contains a heavier charge. Nothing smaller than a No. 6 should be 
used with any of the explosives used on the farm because strong caps 

Insure complete detonation, 

Increase the execution of the explosive, 

Ofifset to some extent deterioration, due to improper storage. 

Prevent the loss of the charge by burning. 




A DU PONT BLASTING CAP 

Blasting caps are packed in tin boxes 
containing 100 caps. From 5 to 50 boxes are 
packed for shipment in wooden cases. They 
may be exploded by shock, heat or sparks, so 
must be kept away from fire. They are 
weakened by moisture and therefore must be 
stored in a dry, cool place, and should always 
be carefully handled. box of du font blast- 

^ -^ , , . . . , ING CAPS 

Caps are used only m connection with 
safety fuse, to which they must be securely fastened. This should be 
well done with an approved Du Pont Cap Crimper described on the 
following page. 

FUSE 

Safety Fuse is a thin chain of powder, wrapped in a covering 
of jute or cotton yarn, or in tape. Its purpose is to bring a spark 
to a cap us2d for detonating a charge of high explosives. Many 
grades are made for dififerent purposes. The ones most used for 

15 




farm work are Charter Oak and Beaver for dry or moist work, and 
Crescent for wet work. 

Fuse is packed in a double roll, one 
fitting inside the other, each 50 feet long. 
Each double roll of 100 feet is wrapped 
separately. It is packed for shipment in 
wooden cases containing from 500 to 
6,000 feet. 

Fuse should always be kept dry and 
should be stored in a cool, dry place. If 
stored in a damp place it becomes damaged after a time and may fail 
to burn. If stored in a hot, poorly ventilated place, as for example, 
close under the roof of a small shed, in summer time, it may be dam- 
aged either by becoming soft and oily or by drying out and becoming 
so hard and brittle that it will break when unrolled. Fuse may become 
stiff and brittle in cold weather. When in this condition it should be 
warmed before being unrolled. 



ROLL OF S.^FETY FUSE 



CAP CKIMPEKS 

Du Pont Cap Crimpers are made especially for securely fastening 
caps to fuse and are necessary wherever blasting is done with cap and 
fuse. The process of waterproofing is well started by the crimp made 
by these crimpers. Caps are often crimped by other means, which are 




DU PONT No. 2 CAP CRIMPER 

dangerous and unsatisfactory. The crimper now sold by this Company 
is the result of years of experimentation, and is the best ever offered the 
public. It is supplied with a pair of jaws for cutting fuse. 

DU PONT ELECTRIC BLASTING CAPS 

These, like the cap and fuse, are for detonating charges of high 
explosives. The explosive charge is contained in a copper cylinder 
quite similar to the ordinary blasting cap, but the explosion is caused 
by an electric spark brought along a pair of small copper wires instead 
of a powder spark from fuse. In strength they are the same as the 
ordinary caps of the same number. The No. 6 strength is the one 
adapted to farm work. 



16 




It is only by the use of electric caps that a number of charges 
can be fired at the same time, so they must be used in ditching in dry 
ground, in blasting large stumps and boulders, or any other work 
requiring a number of simultaneous explosions. .^ 

Du Pont Electric Blasting Caps, like blasting caps, can be exploded 
by shock or heat, and therefore must be handled in exactly the same 
way. The same precautions regarding storage and handling as given 
for blasting caps should be strictly observed. Never attempt to pull 
the wires out of their setting or investigate the contents of Du Pont. 
Electric Blasting Caps. 



A DU PONT ELECTRIC BLASTING CAP, 
SHOWING WIRES 



Electric Blasting Caps reduce the chances of misfires, save time, 
eliminate delayed or premature explosions and in a good many instances 
save dynamite. 

The wires attached to the caps range in length from four feet to 
thirty feet, but it is seldom that anything longer than a four or six 
foot length will be needed in farm work. These lengths are packed in 
lots of fifty in strong paper cartons. Ten cartons are packed in a 
wooden shipping case. 

DU PONT BLASTING MACHINES 

Du Pont Blasting Machines are small, portable electric generators* 
built for generating current to fire electric blasting caps. The mechan- 
ism is operated by a rack bar or plunger protruding through the top 
of the machine. When operating, this bar is pulled up as far as pos- 
sible, and then forced down with a quick, hard thrust. This sets in 
motion the armature and builds up the current until the bottom is 
reached, when the connections are automatically completed and the cur- 
rent flows out through the leading wires to the electric blasting caps 
placed in the charges of explosives. In use the rack bar should be 
forced down as hard as possible, the operator using both hands and all 
his weight. 

In practical operation the machine should be placed on a firm or 
solid place to prevent both machine and operator tipping over. 

The current is conducted, from the machine to the blast by copper 
wires attached to the two wing-nut binding posts on the- machine. 
While the machines are built for rough use and every precaution is 

* The pocket size is a magneto and is operated by twisting the handle. 

17 



taken to make all parts strong, they are likely to be damaged by 
exposure to the weather, and should be wiped off and put in a dry 
place when no longer in demand. 






Pocket Size No. 3 No. 6 

RELATIVE SIZES OF DU PONT BLASTING MACHINES 

Blasting machines should be tested occasionally with a Du Pont 
Rheostat, to be sure that they are working up to standard capacity. A 
full description of the Rheostat and its use will be sent on application. 

Du Pont Blasting Machines are built in six sizes so that a selection 
can be made to suit the demands of all classes of work. 

SIZES AND CAPACITIES OF DU PONT BLASTING MACHINES 



Size of Machine 


Capacity — Number of 

Electric Blasting Caps 

Copper Wires 


Used For - 


No. 1 
" 2 

" 3 

" 4 
" 5 
" 6 


1 to 5 
1 " 10 

1 " 30 
1 " 60 
1 " 100 
1 " 150 


Stumping and boulder blasting. 
Stumping, boulder blasting, and small 

ditch jobs. 
All. classes of general work. 
Large ditches. 
Large ditches. 
Large ditches. 



For stumping, boulder blasting, loosening soils to assist digging 
and similar work the No. 2 machine will be found entirely satisfactory. 
Larger blasts having an increased number of charges will require a 
larger size, but those larger than No. 3 are seldom needed except on 
large contracting jobs. Even very long ditches can be blasted in 
sections with the No. 3 machine. 



18 



LEADING WIRE 



Leading wire is insulated copper wire for conducting the current 
from the blasting machine to the blast. The Du Pont leading wire has 

a strong insulation especially suited to 
the rough usage it must receive. It is 
sold in coils of 200 feet, 250 feet, 300 
feet and 500 feet. There are two kinds, 
Single and Duplex. In the Duplex 
Wire, the two wires are bound together. 
Single Leading Wire weighs about 
two pounds to the hundred feet, and Duplex Leading Wire weighs four 
pounds to the hundred feet. Leading Wire is sold by the pound. The 
double wire will be found most satisfactory for stumping and boulder 
blasting and the single wire for ditching. 




Du Pont Leading Wire 




DUPLEX LEADING WIRE (ACTUAL SIZE) 



DU PONT CONNECTING WIRE 

Connecting wire is used to complete the circuit 
when the holes or charges are placed too far apart for 
the electric blasting cap wires to reach. It is sold in one 
and two pound spools. A one-pound spool of No. 20 
wire holds about 210 feet. 




Du Pont Connecting 
Wire 



USE OF THE GALVANOMETER AND RHEOSTAT 

The Du Pont Company manufactures an instrument for testing 
blasting circuits, called the Du Pont Galvanometer. This is a very 
ingenious and useful instrument, and saves much time in locating 
breaks in electric circuits. For instructions as to its use ask for our 
Galvanometer Booklet. The Rheostat is a simple instrument used for 
testing blasting machines. 

19 



Tools Used in Agricultural Blasting 

The tools needed, for agricultural blasting are very few and simple. 
They are often to be found on the farm, but if .not they can be quickly 
made at little cost by a blacksmith. An elaborate outfit is seldom needed 
even on large j.obs. 

TAMPING STICK 

A tamping stick is used to try out the holes before loading to 
see that they are properly placed and to a sufficient depth, and not 
stopped up; to place cartridges of explosives in bore holes; and to 
tamp soil on top of the charges. It must be of wood, with no metal 
parts. Its length should be a little greater than the. depth of the holes 
to be loaded, and its diameter not smaller than that of a cartridge of 
dynamite, 1% inches: 



null itT III •^ jMmjfAj</«=.ti. - i7' iiii- ii.- imj jii 

FIG. 2. HOME-MADE TAMPING STICK 

An excellent one can be made of an old hoe, rake or shovel handle, 
or when a very long one is needed, from a sapling. 

SUBSOIL PUNCH 

For driving holes for subsoil blasting, tree planting, for ditching 
in hard soil, and for Toad grading, a subsoil punch is needed. This 
should be of lJ/2-inch round or octagonal steel, and a few inches longer 
than the depth of the holes. The point should be drawn out in the 
shape of a rather blunt pencil point. This is driven into the ground by 
means of heavy hammers or sledges. 



FIG. 3. STEEL SUBSOIL PUNCH 

CROWBAR 

A crowbar will be found convenient for making holes under 
stumps and boulders, for ditch blasting, and occasionally for subsoiling 
or tree planting. 

A satisfactory crowbar for this work can be made out of an old 
buggy axle by cutting ofif one spindle and forging a wedge or chisel 
point. 

20 



SOIL AUGER 

The soil auger is used for making holes for stump and boulder 
blasting, for deep drainage, and for other holes hard to make with a 
punch. While it can be used for subsoiling it is not as fast as the 
subsoil punch. It should be 1^ or 2 inches in diameter. 

The bit may be welded to a solid steel shank that will make the 
auger at least five feet long, if for stump or boulder blasting. For 
deeper holes the shank can be made of ^s or yi inch gas pipe in sections 
of 2 or 3 feet in length, so that it can be extended by adding more sec- 
tions. The handle is made of a pipe "Tee" and two short pieces of 
pipe for grips. 

A good type of auger head can be easily made by a smith. The 
shank is flattened out and welded into a sleeve socket. The handle 
proper should be of wood and only long enough to make turning easy. 

Worn-out wood augers make fairly good soil augers for small jobs, 
but where there is much work to do it will pay to get the speciaj soil 
augers shown below. 



FIG. 4. 



SOIL AUGER WITH SECTIONAL HANDLE MADE OF 
Ji-INCH GAS PIPE 



WOOD AUGERS 

Wood augers are used by the blaster for boring into the tap roots 
of fat pine stumps, and for log and stump splitting. They should be 
both heavy and sharp. The shank for stump blasting should not be 
less than five feet long. 



OTHER TOOLS 

Heavy hammers are needed to drive the subsoil punch, and a mat- 
tock and shovel can be used for a number of purposes. For blockhol- 
ing rock a hand drill and hand hammer will be needed. For jobs where 
there is much rock drilling to do, the use of power drills is recom- 
mended. They are not needed, as a rule, on small jobs. 

21 



SPOON 

A blasting spoon made by flattening and cupping the end of a 
j4-inch steel rod, as shown in the accompanying cut, is very convenient 
for enlarging bore holes, removing pebbles from holes, and for remov- 
ing tamping from misfired holes. 







=7 ■£ 



FIG. 5. 



A GOOD TYPE OF SPOON FOR CLEANING OUT THE 
BOTTOMS OF BORE HOLES 



MAKING BORE HOLES IN HARD GROUND 

In performing his work, the agricultural blaster must make many 
holes in hard ground for subsoiling, tree planting, stumping, ditching, 
and other purposes. The subsoil punch is undoubtedly the best tool 
for holes not more than thirty-six to forty-two inches in depth. When 
deeper holes are needed, the punch can be used to start the hole, which 
can be deepened by means of a good soil auger. The use of a little 
water often facilitates punching and boring. 




FIG. 6. THE SUBSOIL PUNCH IS LOOS- 
ENED BY POUNDING ON THE SIDES 
NEAR THE GROUND. WHEN THIS DOES 
NOT LOOSEN IT SUFFICIENTLY, A CHAIN 
IS LOOPED AROUND THE TOP SO THAT 
A CROWBAR OR POLE CAN BE USED AS 
A tEVER. THIS ARRANGEMENT IS USED 
TO THE BEST EFFECT ON ALL AGRICUL- 
TURAL BLASTING 







22 



Blasting 



When dynamite or other high explosives detonate, the small vol- 
ume of solid is converted immediately into a volume of gas many times 
greater than the solid. If the explosive is unconfined the expanding 
gases v^fill waste themselves in the air, but if it is confined there is a 
great pressure exerted on the holding material, which if not too strong, 
will be shattered or blown away. 

The force of the gases is equal in all directions. If the desire is to 
blow a boulder or stump into the air the charge is placed below the 
object. The best shattering is obtained if the explosive is placed in 
the material to be broken so that the force is exerted on it equally in all 
directions. This is applicable in blasting soils and blockholing boulders 
or in splitting stumps. 

While the gases exert an equal pressure in all directions they try 
to escape by the easiest route or along the line of greatest weakness. If 
the tamping is omitted or is insufficient the tendency will be to blow out 
through the bore hole. If a hole is placed to the side of a stump the 
tendency will be to blow out through the more easily lifted soil. The 
aim should always be to make the easiest way out directly through the 
material to be moved or shattered. 

DETONATION 

As has already been explained, dynamite is fired or "detonated" 
by means of the shock from a blasting cap or electric blasting cap, 
either of which is known as a detonator. 

In order that the detonation may be complete, or in other words, 
that the full strength of the explosive be developed, the detonator 
should be placed inside the charge, with its closed or "business end" 
pointed toward the main bulk of the charge. 

PRIMING WITH CAP AND FUSE 

The act of placing the detonator in the charge is known as "prim- 
ing" and the cartridge of explosive with the detonator in it is called a, 
"primer." 

ATTACHING THE BLASTING CAP TO FUSE 

Examine your dynamite and see that it is not frozen. Frozen dyna- 
mite is hard and rigid, and dangerous to handle ; when thawed it is soft. 
Next examine your fuse, see that it is not stiff and brittle; if in this 
condition it is advisable to warm slightly, and cut the required length 

23 



from the roll with a sharp knife, hatchet or cap crimper. The cut 
should be made squarely across and not diagonally (1, Fig. 7). Some- 
times in the cutting the end becomes flattened, thereby making the end 
of the fuse too large to enter the blasting cap. When this happens 
squeeze the end round with index finger and thumb. Open the cap box 
and allow one cap to slide gently out to be grasped in the fingers (2, Fig. 
7) ; but, under no circumstance, pick a cap out of the box with a piece of 
wire, stick, or other hard substance. See that there is no grit or trash in 
the cap. Slip the end of the fuse gently into the cap until it is against 
the charge in the bottom (3, Fig. 7). Do not twist the fuse as the fric- 
tion might cause a premature explosion. Then take the cap crimper and 
fasten the cap to the fuse with a crimp near the open end of the cap 
(4, Fig. 7). These operations are not dangerous but should be done 
carefully. If the primer is to be used in a wet hole smear a little hard 
tallow, soap or similar substance, around the top of the cap to insure 
against water leaking in and ruining the cap before it is fired. Never 
use oil or light grease as these will penetrate the fuse covering and 
ruin the powder. The cap is then ready to be inserted into the dynamite. 
There are two reliable and satisfactory ways of doing this: In 
the Side; and In the End. Never lace the fuse through the cartridge 
when using either method. 





1. Cut off a sufficient length of fuse. 



2, Take one cap from the box with the 
fingers. 





3. Slip cap on end of fuse. 



4. Crimp cap to fuse with cap crimper. 



FIG. 7. ATTACHING A BLASTING CAP TO SAFETY FUSE 
24 



Priming Cartridges in the Side. — This is done by punching a hole 
diagonally into the side of the cartridge (1, Fig. 8) near the end and 
pointing toward the center, to a sufficient depth to receive the entire 
cap. Insert the cap with fuse attached and tie it there with a piece of 
cord, wrapping it firmly around both the fuse and the cartridge (2, 3 
and 4, Fig. 8). This method has the advantage of leaving a good place 
to place the tamping stick in seating the primer in the hole, but, for 
small holes, has the disadvantage of a slight increase in size. This 
method is the one generally used by agricultural blasters. 





"^ 



1. Punch a hole in side of cartridge with 
handle of cap crimper. 



2. Tie cord around fuse. 





3. Complete by tying around cartridge. 



4. Completed primer ready to load. 



FIG. 8. PRIMING A CARTRIDGE IN THE SIDE. (A HIGHLY SATISFACTORY 
METHOD FOR MOST CLASSES OF AGRICULTURAL BLASTING) 

Priming Cartridges in the End. — This is done by punching a hole 
directly into the end of a cartridge (1, Fig. 9), through the paper shell 
and to a sufficient depth to receive the entire cap. Into this insert the 



25 



cap with fuse attached and tie it securely as is indicated in 2 and 3, Fig. 
9. This method has the advantage of the smallest possible diameter and 
places the cap in the best possible position; but has the disadvantage of 
leaving little room for seating the tamping stick. It is largely used in 
blockholing boulders and for other small bore holes. 





1. Punching hole with handle of cap 

crimper. 



2. Tie cord around cartridge and 




3. Then around fuse. 
FIG. 9. PRIillNG IN END OF CARTRIDGE 

The greatest care should always be exercised in making primers, 
for if the work is carelessly or incorrectly done, the best results cannot 
be expected and the danger of accidents is increased. 




FIG. 10. CRIMPING A BLASTING CAP TO A PIECE OF SAFETY FUSE 

26 




PRIMING WITH ELECTRIC BLASTING CAPS 

When electric blasting caps are used they may be inserted into the 
dynamite as has been described for caps and fuse. Many blasters, how- 
ever, prefer to use a slightly faster method, which has been found 
entirely satisfactory. 

Punch a hole from the center 
of the end of the cartridge in a 
slanting direction so that it will 
come out at the side 2 or 3 inches 
from the end, insert the end of the 
doubled over wires of the electric 
blasting caps, loop these around 
the cartridge, after which another 
hole is punched in the top a little 
to one side of the first and straight 
down. The entire capsule is in- 
serted in this last hole, and the 
slack taken up on the wires, with 
the result that you have a primer 
where the wires do not cross each 
other at any point and the capsule 
is lying nearly in the axis and the 
cartridge hangs vertically, so that 
it is possible to load in the bore 
hole without its being caught on 
any roughness. 

Never half-hitch the wires 
around a cartridge of dynamite, 
for upon pulling the wires or lowering the primer into the bore hole, the 
insulation may become worn through where the wires cross, thus allow- 
ing the bare wires to come in contact, causing a short circuit and misfire. 





FIG 11. A QUICK METHOD OF M.MCING 
PRIMERS WITH ELECTRIC BLASTING 
CAPS 



The holes can be punched in the dynamite with the handle of the 
cap crimper, or with a wooden awl, and should always be about ^ inch 
deeper than the length of the entire cap. 

When the primer is to be of only half a cartridge, as in subsoiling, 
it is good practice to punch a hole in each end of the cartridge and cut 
the cartridge in two before inserting the caps. 

The cap should always be firmly secured to the dynamite cartridge, 
otherwise they may become separated and a misfire result. 



27 



CUTTING A DYNAMITE CARTEIDGE IN HALF 

When small charges are desired it becomes necessary to cut 
cartridges in half. This should be done with a sharp knife. Hold the 
cartridge firmly in one hand and the knife in the other. Giving the car- 
tridge a rotary motion, cut the paper all the way around and then bend 
the cartridge slightly, when it will come apart just where the paper is 
cut. Never try to cut a frozen cartridge. 




CUTTING CARTRIDGE IN HALF 

MAKING BORE HOLES 

The holes made for loading explosives are called "Bore Holes." 
These should be prepared before the primers are made. The-tools de- 
scribed on pages 19 to 21 are found most useful for making the differ- 
ent kinds of bore holes. Specific advice with regard to their location 
and depth is given in the discussions of the different classes of blasting. 

LOADING 

When the cartridge is primed and the bore hole made, the next 
thing to do is to load. First try the hole with the tamping, stick to 
see that it is open and will permit the charge being placed at the 
desired point. 

When loading small charges, as when only a full or half cartridge 
primer is used for subsoiling or tree planting, start the primed cartridge 
into the bore hole and press it gently into place with the tamping stick. 
See that it is firmly seated in the bottom of the bore hole. 

In pressing a primer into place, do not handle it roughly, as it 
contains the cap and is, therefore, more sensitive and dangerous than 
an unprimed cartridge. 

When the load is to contain a larger amount of dynamite, press 
the unprimed cartridges into place in the bottom of the hole first, and 
place the primer with the cap pointed toward the rest of the charge on 
top. When the bore hole is dry, and it is desirable to have the charge 
concentrated in one place, it is a good practice to slit the sides of the 
cartridges in two or three places and from end to end with a knife so 
that the dynamite can be compacted into a smaller space. The primer 
should not be split. 

28 



In all classes of agricultural blasting the charge should be pressed 
firmly into the bottom of the bore hole so that no air pockets are left 
as they weaken the action of the explosives. When bore holes are wet, 
it is not advisable to slit cartridges. 

For most work it is necessary to determine the corre"ct amount of 
explosives by a few test blasts. This is pointed out in the special para- 
graphs on the different classes of blasting. 



TAMPING 

Closing the top of the bore hole after the charge is placed is for 
the purpose of more closely confining the charge to insure better work 
and is called "Tamping." It should be made as tight as possible, so that 
the gases will not blow out as through the muzzle of a gun. 

To guard against danger of prematurely detonating the charge, the 
first 5 to 8 inches of tamping should not be packed with any consider- 
able force, but should be gently firmed. When this amount of lightly 
tamped material covers the primer, the rest of the tamping should be 
made as hard as possible, using the wooden tamping stick in one hand. 

jse "^^ Tuse 



^ BLASTING GAP i 

j^-^OYNAMlTE CARTRIDGE^og 
PRESS CARTRIDGE DOWN GENTLY: DON'T POUND 



i ^ BLASTING CAP ^ 

^ tj .^DYNAMITE CARTRIDGE til ^ 

PUT IN 3 TO 5 INCHES OF EARTH AND TAMP LIGHTLY 



LIGHT TAMPlriG 







y^ D VWAMITE CARTRIDGE l>« , 

AIVl&-FIRMLY_To'THEjroEAND ITJS RtADYjTO FlRe 




TIGHT TAMPING 



1 
- LIGHT TAMPING 
' BLASTING CAP I 

L , ^_ _ ^ , [J^ DYNAMITE CARTRIDGE taS 

UIGhT FuSE AND RETIRE TO A SAFE DISTANCE 



FIG. 12. DIFFERENT STEPS IN LOADING AND TAMPING A HOLE 

Moist clay, free from gravel and clods, makes good tamping mate- 
rial. Free running sand or moist loam is also good. In wet work, when 

29 



a foot or more of water covers the charge in shallow holes, it will not 
be necessary to add other tamping, as the water will hold the charge 
sufficiently tight. Loading and tamping should be done in such a way 
that no open-air spaces are left. 

When using soil for tamping, the hole should be tamped full. Do 
not allow sharp pebbles or stones to fall in the hole during loading and 
tamping. 

Before beginning tamping it is well to measure the depth from the 
surface to the top of the charge, so that if the tamping must be removed 
to get at a misfire there will be no danger of disturbing the primer. It 
is a good practice, especially where heavy charges are used, to place 
two inches of paper or dry leaves immediately over the primer, so that 
they can be used as a safety marker should the tamping need to be 
removed for any cause. 

FIRING 

Exploding the charge is called "Firing," and can be done either 
by means of caps and fuse or by electric blasting caps with a blasting 
machine. When cap and fuse are used cut the fuse long enough to 
reach about 3 inches out of the bore hole and to enable you to retire 
to a safe distance. Fuse burns on an average of two feet per minute 
and a sufficient length should be used to permit of the blaster reaching a 
safe point before the explosion. When using electric blasting caps the 
leading wire should be long enough to enable the one who operates the 
blasting machine to be outside the danger zone. No blast should be 
fired until persons, animals and vehicles are well out of range. 

When reliable explosives and blasting supplies are used, and the 
primers properly made and placed, misfires should seldom occur. When 
using cap and fuse, and a misfire is noted, do not return to examine 
it at once, as an injured fuse may be burning slowly and delaying the 
shot. It is better to wait until the next day, if possible. 

When using electric blasting caps there is no danger of delayed 
shots and less likelihood of misfires. When one does occur, disconnect 
the wires from the blasting machine, and it will be safe to return imme- 
diately to the blast for investigation. Never connect the wires to the 
blasting machine until it is' time to fire, and guard against a careless 
person tampering with the machine and leading wire while loading 
shots. 

In selecting a safe place to watch a blast, do not get behind a tree 
or building, but stand in the open at a safe distance from the blast, 
so that you can see the flying fragments and dodge any that may come 
beyond reasonable bounds. Do not have the sun in your eyes, as it 
may obscure flying missiles. 

30 



HANDLING A MISFIRE 

The use of high grade explosives and caps and careful loading will 
reduce the dangers of shots failing to fire. When a misfire does occur 
the blaster should be governed by conditions. 

When electric blasting caps are used and one or all of the holes 
fail, disconnect the wires from the blasting machine, and it is safe to 
go back immediately to investigate the trouble. The investigation should 
first consist of a search for broken wires, faulty connections, or short 
circuits. If such are found, make the proper repairs, reconnect the 
leading wires and operate the blasting machine. Many so-called fail- 
ures are the result of poor connections or connections being in contact 
with wet ground or other conductive material. 

When caps and fuse are used greater care must be exercised. It 
is never safe to go back immediately to a delayed shot that is primed 
with cap and fuse. The fuse may have been injured in tamping, and 
instead of burning rapidly may smoulder for a long time, then re- 
ignite the powder in the lower end of the fuse and fire the blast. The 
interval of waiting should be as long as possible, preferably until the 
next day if the firing is done in the afternoon. In all cases it should be 
several hours. When lighting fuse be sure that the powder column is 
on fire shown by the "spitting" out of the flame, as time may be wasted 
in waiting for a blast whose fuse is not even lighted. 

If the hole is untamped or is tamped with water, make up another 
primer, place it on top of the charge, and fire. If the ground is soft 
and wet put down another charge far enough away for drilling in 
safety, but close enough to cause detonation by concussion. When this 
is not possible there are two methods of relief. The tamping can be 
carefully removed almost down to the charge with a spoon and hard- 
wood probe. Great care must be exercised, especially when the cap is in 
the top cartridge of the charge, to prevent danger of firing the cap by 
friction or impact. 

When it is necessary to blast out a misfire by drilling and charging 
a second hole, great care should be exercised. Such a hole must be far 
enough away from the charge to make drilling and loading safe, but 
must be close enough to insure the old charge being blown out together 
with the rock or confining ground. 




FIG. 13. USE OF A PAPER PLUG TO BEGIN TAMPING 

31 



When for any reason, misfires may be expected, a. good practice is 
to use a wad of paper or dry leaves immediately over the charge of 
explosive and pack the tamping on top of this., If it becomes necessary 
to remove the tamping, this dry material makes an excellent index of 
just how far down it is safe to remove the tamping. 

AH misfires should be placed under the direction of a careful and 
experienced workman, who should make his examination in a slow, 
methodical manner before beginning the. work of repriming, and no 
other person should be allowed to remain near him, as their presence 
or suggestions are likely to cause confusion. 

As stated before, only the best explosives and supplies should be 
used, as they decrease the dangers of misfires, which always delay the 
work and increase the cost of the job. 

The adoption of electric blasting will result in a decrease in delayed 
or missed fires, and is to be recommended on all road work and 
blasting where passing persons might be injured. 

BLASTING BY ELECTRICITY 

Large boulders and stumps with spreading roots can be blown 
out and broken up more thoroughly and with less dynamite if the 
charge is distributed in several holes in different places under the 
boulder or stump and all of these charges exploded at one time. 
Groups of stumps standing close together can also be blasted in this 
way. . In order to dig a ditch satisfactorily, it is always necessary to 
explode a number of charges simultaneously. In dry soils this can be 
done only by electric blasting. In well sinking and other kinds of 
blasting it is of advantage to explode a number of charges at one 
time, as each tends to help the other. The only way in which several 
charges some distance apart can be exploded at exactly the same 
time is by the electric method of blasting. Electric blasting may be 
applied to all of the work described in this Handbook, but it is gen- 
erally unnecessary and more expensive, except in the blasting just 
described. 

The equipment for blasting by electricity, in addition to the 
explosive, consists of 

Electric Blasting Caps Leading Wire 

Connecting Wire Blasting Machine 

When the charges have been primed with electric blasting caps 
and tamped, the two copper wires protrude from the ground over each 
charge. These two wires should be separated and one of them con- 
nected to one of the wires of the next electric blasting cap on one 
side and the other one should be connected in the same way to one of 

32 




FIG. 14. 



METHOD OF CONNECTING WIRES FOR 
ELECTRIC BLAST 



the wires of the electric blasting cap in the hole on the other side. This 
should be continued until all of the charges are connected in a row with 

one free wire extending from the first 
charge and another extending from the 
last charge. These loose wires are con- 
nected to the wires leading to the 
blasting machine. This is 
called "connecting in 
series.'' If the holes 
are too far apart for 
the electric blasting 
cap wires to reach 
between them, pieces 
of connecting wire 
are used. 
Connections are all made by twisting bare wire ends securely 
together. All wire ends should be scraped with a knife so that they 
will be free from grease or corrosion when connections are made. 

All bare joints or other uncovered places in the wires must be kept 
away from water or damp ground. This can be accomplished by put- 
ting a stick, block of wood, or stone under the wire to hold it off of the 
damp ground. 

Always be sure that there is a complete circuit of wire offered for 
the passage of the electric current, otherwise the blast will not fire, for 
the current must pass through each electric blasting cap in order to 
ignite it. 

Should there be any bare joints resting upon damp ground or in 
water, or should one bare joint touch another, there is a likelihood of a 
short circuit through which the electric current will pass instead of 
around the entire blasting circuit where it encounters greater resistance 
to its passage. 

A very convenient and accurate instrument for testing a circuit to 
ascertain whether there are any breaks in the connections or wires, and 
a great help and time saver in locating these breaks is the Du Pont 
Galvanometer mentioned on page 18. 



33 




For the best conservation of man power and the successful utiliza- 
tion of land, all fields must be cleared of stumps and boulders. 



Well-Cleared Fields 

Have all the land open for the 
production of crops ; 

Permit the use of the heaviest 
and most effective labor-saving 
machinery ; 

Reduce the cost of field oper- 
ations to a minimum ; 

Are attractive in appearance 
and increase the interest of the 
ovk^ner as well as the selling value ; 

Permit the destruction of 
weeds and crop pests by ordinary 
tillage operations ; 

Make possible the adoption of 
systems of tillage that will prevent 
erosion. 



Stumps and Boulders 

Occupy space and reduce the 
actual size of fields ; 

Prevent the satisfactory use 
of modern farm machinery ; 

Increase the cost of field 
operations ; 

Are unsightly and reduce the 
actual producing and selling value 
of the farm ; 

Provide breeding places for 
weeds and crop pests ; 

Increase the dangers of ero- 
sion by preventing satisfactory 
plowing. 



The conservation of Man Power finds most ready application in 
land clearing, provided logical methods are employed. The best meth- 
ods of clearing are with explosives and pulling machinery. Each 
method has its advantages and is particularly adapted to certain classes 
of land or conditions. In many cases the greatest economy in clearing 
is by combination methods — or the use of both explosives and pullers. 
The following paragraphs cover these details quite fully. 

34 



Blasting Stumps 



The root systems of the different forest trees are subject to a con- 
siderable number of variations, due to the class of tree, the soil and the 
depth to sheet water. Ordinarily, forest trees are divided according 
to their root systems into three classes. These are : Those having tap 
roots; those having no tap roots, but only lateral fibrous roots; and 
those having both a small tap root and many lateral roots. When trees 
that normally develop heavy tap roots are grown on soils where the 
ground water level is very near the surface, the tap root will be mate- 
rially shortened or entirely wanting. Lateral-rooted trees growing in 
loose soils not troubled by bad drainage, may send heavy lateral roots 
to considerable depths. 

Several factors very materially influence the blasting of stumps, 
notable of which are : 

The character of the root, whether tap or lateral. 

The nature of the soil, whether sand or clay, as the kind of 
soil has much to do with the resistance offered to the dynamite. 

The moisture content of the soil. 

The state of preservation of the stump, whether sound or 
partially decayed. 

Freshly cut or green stumps are much harder to blast than those 
from which the small roots and bark have decayed. 

Success in stump blasting is a matter of common-sense and discre- 
tion, and the work may be undertaken by anyone of reasonable intelli- 
gence, who will first try a few experiments on the small stumps, and 
follow out carefully the rules laid down on the following pages. 

BLASTING TAP-ROOTED STUMPS 

There are two distinct methods of blasting tap-rooted stumps. 
The charge can all be placed in a single hole bored into the root, or it 
can be placed in one, two or three holes alongside the tap .root. When 
two or more holes are used, electric firing must be practiced. Each 
method has its advantages. Placing the charge in the stump requires 
more labor and a smaller charge, while the other method requires but 
little labor and a greater amount of explosives. The first method 
reduces the stump and tap roots to smaller fragments, and is generally 
used by those blasting stumps for distillation. 

35 



Loading in the Tap Boot. — In placing the charge in the root a spade 
is used to remove a little soil so that the tap root is exposed to a depth 
of a foot or more. The hole is bored diagonally downward through 
the center of the root, using a heavy IJ/^ or 2 inch wood auger. This 
should reach well below any possible depth of subsequent tillage, and 
more than half way through the root. 

In loading it is best to use a half -cartridge primer and remove the 
rest of the charge from the paper shell. Pack the charge firmly in 
the bottom of the hole and press the primer firmly against it. The 
hole should then be tamped tight up to the very collar. Better results 
will be obtained if the soil is pressed firmly back into the hole made to 
expose the tap root (Fig. 15). 



jj^,fh>- ^^*t^y^ 



ORiJ^^SJi^.. 




FIG. 15. METHOD OF BORING AND 
LOADING A TAP-ROOTED STUMP FOR 
A CAP-AND-FUSE BLAST. THIS LOCA- 
TION OF THE BORE HOLE IS BEST 
WHEN THE BORING IS DONE WITH 
HAND AUGERS 



The charge will vary from a half -cartridge prim.er for small roots 
to three or four cartridges for very large solid stumps. Stumps having 
decayed or hollow tap roots should not be loaded in this way, as they 
can be gotten out better by two or more charges placed around the 
tap root. 



FIG. 16. WHEN POWER BORING MA- 
CHINES ARE USED. NO EARTH IS 
SHOVELED, AND THE HOLE IS 
STARTED INTO THE WOOD SLIGHTLY 
ABOVE THE SURFACE OF THE 
GROUND 



When electric boring machines are used it will not be necessary 
to use a shovel, as the hole is started in the root immediately at the 
surface of the soil, and can range almost straight down into the tap 
root (Fig. 16). This is the method of loading used by many who blast 
large numbers of pine stumps for distillation. 

To split fat pine stumps to facilitate burning, the holes are bored 
and loaded as has just been described, but lighter charges of Farm 
Powder are used. 

The explosive recommended is Red Cross Farm Powder. 

36 





Loading Around the Tap Root. — When placing the charge between 
the tap root and the subsoil, the wood auger will not be rieeded, as the 
holes can be made faster with a subsoil punch, crowbar or soil auger. 
( See pages 19 and 20. ) 

In this method much depends on the depth and location of the 
bore holes, which should be not less than three feet deep, and usually 
more. The charges should be snug against the tap root, so that they 
will lie immediately alongside the wood. 

When but one hole is used for blasting small or old stumps, the 
charge should seldom be less than IJ/2 cartridges. If the holes are 
dry all the cartridges except the primer should be slit from end to end 
and packed tightly in the bottom of the hole. The tamping must be 
tight. Such a charge can be fired with cap and fuse. In clay and clay 



FIG. 17. FOR BLASTING TAP-ROOTED 
STUMPS WITH DISTRIBUTED 
CHARGES AND ELECTRIC FIRING. ■^'^-^"^'-^^ 
TWO OR MORE HOLES ARE PUNCHED , 
ALONGSIDE THE MAIN ROOT AND ; 
LOADED. ONLY ELECTRIC BLAST- ; 
IXG CAPS CAN BE USED FOR THIS ? 
PURPOSE 



loam subsoils Red Cross Farm Powder should be selected, but in light 
or sandy subsoils Red Cross Stumping Powder or Red Cross Extra 
40 to 50 Per Cent. Dynamite will give better results. In light sand 
soils, loading in the tap root and firing with blasting cap and fuse is 
usually better. 

When for large tap-rooted stumps that are so firmly brace-rooted 
that the single hole method of blasting is ineffective, two or more 
charges are distributed around the tap root. The same care should be 
exercised in putting down the holes, and if the stumps are large the 
holes should be not less than four feet deep. Only electric caps can be 
used. The charges will vary from Ij^ to 2]A cartridges for each hole. 



BLASTING SEMI-TAP-ROOTED STUMPS 

A\'here stumps have a tap root of medium size and a heavy set 
of lateral roots, the loading will be intermediate between the loading 
for tap-rooted and lateral-rooted stumps. This loading is practically 
the same as that shown in Fig. 17, the chief difiference being that an 
occasional charge will be needed under the heavier brace roots. (See 
Fig. 19.) 

17 




BLASTING SMALL LATERAL-ROOTED STUMPS 

When stumps have no tap root, but only lateral ones, the load- 
ing will depend on the nature of the soil and the size and state of 
preservation of the roots. When they are small or the roots are 
partly decayed the charge can all be placed in a single hole started a 
little way back from the stump and sloped under the part of the stump 
that will be hardest to lift (Fig. 18). The charge will run all the way 
from less than a cartridge to several cartridges. 

Where the subsoils are tight and ofifer good resistance Red Cross 
Farm Powder will prove itself to be the most satisfactory and eco- 
nomical explosive. In loose sandy soils 40 or 50 per cent. Red Cross 
Extra Dynamite or Red Cross Stumping Powder will be better. 

^CLAY TAMPINQ 

M_^(C*Iii..|(^.Jlj^[||||||j||||j|j|||||||)||l|[||||^y^.l//..J^\ 

FIG. 18. CORRECT METHOD OF LOAD- 
ING A SMALL STUMP FOR A SINGLE 
CHARGE BLAST. THE CHARGE MUST 
BE LOADED WELL UNDER THE HARD- 
EST PART TO LIFT, AND WELL 
TAMPED 



Here, again, the depth of the holes will play an important part. 
If they are too shallow the blast will only split the stump and fold 
the parts back without blowing them out. Shallow loading is advisable 
only when the stump is to be split and then pulled as is described on 
page 43. It is seldom for blasting the stump out entire, that the loading 
should be shallower than 30 inches, and, if the stumps are hard to blast, 
4 feet is better. 

The tool for making holes is a crowbar or a subsoil punch (Fig. 3). 
A soil auger (Fig. 4) is frequently needed for deepening the holes for 
blasting large stumps. 

BLASTING LARGE LATERAL-ROOTED STUMPS 

The use of electric blasting is essential to the best success in blast- 
ing large stumps or those having wide-spreading roots. If the charge 
is confined in a single bore hole, as in Fig 18, the effect will be to split 
and not lift the stump, but if the same or a smaller charge is distributed 
in several well-located holes, the blast fired by electricity will lift the 
stump perfectly. The number and location of the holes must be gov- 
erned absolutely by the individual stump. For stumps slightly larger 
than can be lifted by a single charge, two holes will usually be sufficient. 
These should be on opposite sides of the stump, and should be inclined 

38 



under the stump. For larger stumps three or more holes should be 
used. One of these should be under the center of the stump and the 
rest so placed around the outer edge as to form a circle under and 
around the holding roots, as is shown in the two accompanying cuts 
(Figs. 19 and 20). 

Care should be exercised to get the center or main charge well 
under the stump. This is needed for lifting and splitting the heavy 
part. The other charges should be distributed under the large roots, 
and may be some distance away from the stump. For this kind of 
blasting only electric blasting caps can be used. 



^i 





A B 

FIG. 19. METHOD OF LOADING LARGE LATERAL STUMPS WITH DISTRIBUTED 
CHARGES, FOR AN ELECTRICALLY-FIRED BLAST. "A" SHOWS WHERE THE 
HOLES SHOULD BE STARTED AND, IN A GENERAL WAY, HOW THEY SHOULD 
POINT, AND HOW THE WIRES ARE CONNECTED IN SERIES TO THE LEADING 
WIRE. "B" SHOWS THE LOCATION OF THE HOLES UNDER THE STUMP 



FIG. 20. SHOWING FULL DE- 
TAILS OF LOADING DIS- 
TRIBUTED CHARGES, UNDER 
AND AROUND A LARGE 
STUMP FOR AN ELECTRI- 
CALLY-FIRED BLAST. THE 
LEADING WIRE SHOULD 
NOT BE LESS THAN 250 
FEET LONG 




As in all stump blasting, the holes should be well down into the 
subsoil — not close up to or in contact with the wood. The best tools for 
making the holes are the crowbar and the subsoil punch. Soil augers 
are sometimes used. 

The best explosive for this work is Red Cross Farm Powder, 
unless the subsoil is loose and open, when Red Cross Stumping Powder 
or Red Cross Extra 40 per cent, will be found more satisfactory. 

Each separate charge, or hole, is primed with an electric blasting 
cap. The wires to these caps are connected as is shown in Fig. 20, and 

39 



to the leading wire which is in turn connected to the blasting machine. 
Several stumps can be wired into the same blast and fired togetlier. 

BLASTING STUMPS FROM VERY SOFT SOIL 

For cypress, willow or other stumps in very soft, swampy soil, 
modification must be made in the methods of loading on account of 
the poor resistance ofifered by the soil and the enormous number of 
spreading roots. The holes must be so distributed that not only the 
stump, but all of the main-spreading roots will be blown out down 
below plowing depth. The quicker-acting Red Cross Extra Dynamite 
of 40 or 50 per cent gives best results. To insure the most efficient use 
of the explosives the shots should be fired as soon as possible. 

BLASTING HOLLOW STUMPS 

Many of the stumps are found to be only shells, the heart having 
been entirely rotted away. To blast these successfully drive a bar or 
rod into the soil down through the hollow, and tamp the stump full of 
moist soil, remove the stake and load in the hole left by the post and 
tamp solid. Additional charges placed under the spreading roots should 
be used, and fired electrically. 

FIG. 21. METHOD OF LOADING A LARGE 

HOLLOW STUMP WITH DISTRIBUTED 

CHARGES FOR AN ELECTRICALLY- 
FIRED BLAST. THE ONLY VARIA- 
TION FROM THE ORDINARY LOADING 
OF LARGE STUMPS (FIGS. 19 AND 20) 
IS IN DRIVING ONE HOLE DIRECTLY 
THROUGH THE HOLLOW 

BLASTING STUMPS UNDER WEST COAST CONDITIONS 
Western Fir, Pine and Cedar Stumps 

In the States of Washington, Oregon and parts of California, 
where the rainfall is heavy and the ground in the forests is always 
damp, many of the trees grow to great size — some being eight or ten 
feet in diameter. The roots of these trees usually spread out near the 
surface and do not grow deep into the ground as might be expected, 
tap roots being extremely rare. 

The object when blasting these stumps is not only to split them, 
but to bring out the pieces at one blast, with all of the roots possible, 
because if the charge of explosives is so gauged and located as to split 
the stump, it generally fails to bring out all of the pieces. As the 
principal object is to get out as much of the stump as possible at a 
minimum cost, it is better to blast it out first and then it can be easily 
split afterwards by means of a small quantity of dynamite exploded 
in auger holes. 

40 




The common rule in blasting these stumps is to use one and one- 
half pounds of Du Pont or Repauno Stumping Powder per foot of 
diameter, with stumps up to four feet, when the subsoil is clay. For 
larger sizes from two to two and one-half pounds for each foot in 
diameter should be used. Stumps in gravelly or loose ground require 
one pound more for each foot in diameter. 

The charge of explosives is best placed so that there will be from 
sixteen to twenty-four inches of earth between it and the bottom of 
the stump. This results in the force of the explosion radiating to all 
sides, lifting the stump clear of the ground, and bringing with it the 
greatest length of roots. If the charge is placed too close to the stump, 
the eftect is to split it, leaving the roots to be dug out at extra labor 
and expense. 



FIG. 22. SHOWING LOC.\TION OF A 
SINGLE LARGE BORE HOLE AND 
METHOD OF LOADING LARGE WEST- 
ERN STUMPS, USING BLASTING CAPS 
AND FUSE 






As the large amounts of powder required to blast out a stump of 
this character cannot be contained in a bore hole such as is advised for 
small stumps, a larger bore hole is required. This is usually dug with a 
long-handled tiling spade. The earth is loosened by means of a crowbar 
or long chisel and cleaned out of the hole with a spade. The charge is 
loaded into this large bore hole in exactly the same manner as in other 
holes. 







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THE VACANT THRONE OF A DEPOSED MONARCH IN THE PACIFIC NORTHWEST 

41 



REDWOOD AND BIG TREE STUMPS 

The way to estimate the quantity of Du Pont or Repauno Stump- 
ing Powder necessary to blast out stumps larger than eight feet in 
diameter, is to square the largest diameter in feet, the result being 
approximately the number of pounds required. For example, if a 
stump is eight feet in diameter the charge -of Du Pont or Repauno 
Stumping Powder should be about the square of eight, or sixty- four 
pounds. Stumps less than eight feet in diameter require a little greater 
charge for their size than do the larger stumps, and the rule with 
them is to use as many pounds of Du Pont or Repauno Stumping 
Powder as eight times the largest diameter in feet. On this basis a 
stump six feet in diameter would need about forty-eight pounds of 
powder. However, the successful blasting of these large stumps 
depends greatly on the judgment' of the blaster, and these rules can 
be considered only as a general guide. This can easily be understood 
when it is remembered that, owing to difference in soil or some pecu- 
liarity in the growth of the tree, it sometimes requires the same quantity 
of explosives to properly bring out a stump six feet in diameter as it 
does another one eight feet in diameter. 

In blasting these stumps a trench is dug large enough to permit 
placing the entire charge of explosives directly underneath the center 
of the stump. A little powder blasted in holes punched with a crowbar 
will prove of great assistance in digging this trench, especially when the 
subsoil is clayey. 

The charge should be firmly tamped. Avoid being on the same 
side of the stump as the trench when the blast is fired, as fragments, 
or stones may be thrown with more violence and to greater distances on 
that side. 

***** 

Where there is much heavy stumping and means are available for 
purchasing the needed equipment, the combination methods described 
on pages 43 to 46 are recommended for West Coast conditions. See 
also pages 46 to 49 for methods of piling and disposing of stump 
fragments. 

SPECIAL BOOK FOR THE PACIFIC NORTHWEST 
On account of the differences in explosives recommended for this 
region, and this book being prepared especially for the States lying 
east of the Rocky Mountains, those interested in developing land in 
Washington, Oregon or California should write for a copy of "Devel- 
oping Logged-off Lands of the Northwest." It gives specific advice 
applicable to that part of the country, and should be in the hands of all 
interested in its development. 

42 



APPROXIMATE CHARGES FOR BLASTING STUMPS 

No absolute rule can be laid down giving the required charge for 
blasting stumps of different sizes, but the following, which is based on 
old but solid stumps in firm, dense soil can be used as a basis, making 
variations either way as may be required : 

Diameter of Stumps in Inches 12 18 24 30 36 42 48 

Number of Cartridges of Red Cross 

Farm Powder 3 4 6 7 8 12 15 

If the stumps are green, or if the soil is loose or sandy, these 
amounts must be increased, but if the stumps are partly decayed, lighter 
loading will do the required work. 

These approximate estimates, of course, are based upon the idea 
that Red Cross Farm Powder alone is to be used and that the stump is 
to be blasted out entirely. If the object is to merely break or loosen the 
stump before or after pulling it with a stump puller, then, of course, 
these estimated charges can be reduced to one-third or one-half. 

Each operator can easily determine for himself, by making a few 
experimental shots, what the proper charges will be. Of course, the 
aim should be to do the work with the least possible amount of Red 
Cross Farm Powder. As a starting point, we would suggest using the 
charges mentioned in the table above. They can be increased or 
decreased in keeping with the results of the test shots. 




A TYPICAL PIECE OF WASTE LAND 

43 



FELLING TREES 

The loading for blasting . down standing trees is the same as for 
stumping, with the important difference that heavier loading is required, 
because of the greater weight to be lifted. If this work can be done 
during a high wind, the wind load on the tops of the trees will mate- 
rially assist in bringing them down. When a tree is valuable for saw 
stock it should not be blasted down, as the blast may split the trunk in 
such a way as to ruin it for the sawmill. 

COMBINATION METHODS OF STUMPING 

Stump pullers are on the market operated by hand power, horse 
power, gasoline engines and steam. On clearing jobs large enough to 
warrant the investment in a puller, explosives and a good machine work 
nicely together. All men have their individual tastes and preferences. 
Some swear by explosives and others by stump pullers. A third class 
takes the middle ground, and uses both in conjunction. On the large 
jobs a saving in time and money is effected by the combination; the 
stumps are well shattered; the holes are small; and the final fitting of 
the land made easy. 

This combination method makes use of dynamite for splitting the 
stump and freeing the roots of dirt either before or after pulling. The 
puller is used to draw the roots or stump, the final object being 
to clear the land and dispose of all stump fragments. A large number 
of tests, chief of which are those recently conducted under the direction 
of the University of Wisconsin, have proven that on large areas, the 
use of this method is better than either pulling or blasting alone. 

The advantages of using a puller and explosives in conjunction 
are: 

(1.) A saving in explosives ; 
(2.) A saving in time ; 
(3.) A saving in labor ; 

(4.) Less strain on machinery, horses and harness; 
(5.) Greater ease in handling the stump after it is out; 
(6.) Does away with the disagreeable and time-consuming 
work of clearing dirt off the roots ; 

(7.) Does away with a large part of the work of filling the 
hole. 

When to Pull Stumps, — When horse or other power is available, 
and large numbers of small stumps are to be removed from sandy soils, 
the puller, alone or with a minimum of dynamite, is better and more 
economical than blasting. 

When to Blast Stumps. — When the stumps are scattered, as in old 

44 



cultivated fields ; or when there is but a small amount of clearing to do 
in any one place, as in clearing up small wood lots or corners, the 
advantage is undoubtedly with explosives used alone. This use has 
also proven best for obtaining stump wood in the Stump Turpentine 
industry. 

Dynamite, loaded well below the ground level, should be used 
without heavy pullers for clearing stumps out of orchards. 

When to Use Combination Methods. — The use of combination 
methods is recommended for general clearing operations, not covered 
in the two general recommendations just made, where the stumps are 
either large or green, for under these conditions the most careful work 
must be done to get the desired results with either individual method. 
Occasional failures to blast the stump out entirely and the balls of 
earth on the roots lifted by the pullers are both objectionable. 

A careful study of the local conditions should always be made 
before selecting the necessary equipment. 

BLASTING BEFORE PULLING 

Perhaps the most satisfactory general application of the combina- 
tion method is to blast the stumps and then pull the fragments. The 
loading is done in keeping with Fig. 23. The object is to split the main 
part of the stump and loosen the brace roots from the ground so that a 
minimum of earth is pulled out. The loading should be shallow, so that 
the hardest blow of the blast is directly against the forks where the 
roots branch out from the stump. The charge, which is usually fired 
with a blasting cap and fuse, should be just sufficient to split and loosen 
the stump. 



.4J,.l^kt 




FIG. 23. LOC.MIOX OF A SH.^LLOW 
BLAST FOR SPLITTING A STUMP FOR 
PULLING. THE CHARGE SHOULD BE 
PLACED CLOSE UP TO THE WOOD 
AND SHOULD BE JUST HEAX^Y 
ENOUGH TO SPLIT THE STUMP 



This method is highly satisfactory for green stumps or those hav- 
ing heavy spreading roots, especially on silty loams and hea\ier soils. 

Red Cross Farm Powder is recommended for heavy soils and Red 
Cross Stumping Powder or Red Cross Extra Dynamite 40 per cent, for 
light ones. 

45 



PULLING AND BLASTING 

In this application of the combination methods the stumps are first 
pulled and then blasted to free the roots of dirt and to split the stumps 
so that the)' can be piled and Inn-ned or used for other purposes. It is 
not so well suited to extremely large stumps or those having heavy 
spreading roots as is blasting before pulling. It finds its chief use on 
stumps that have large single roots or on sandy land. 

Blasting Pulled Stumps. — There are three methods of blasting 
pulled stumps : 

(a.) Any cavity or hollow in the stump can be loaded fFig. 24). 
The hole should be well tamped. 




FIG. 24. SHOWING LOCATION OF A 
CHARGE OF E.\PLOSI\'ES IN A HOL- 
LOW-PULLED STUMP 



This method finds ready use when old hardwood stumps are being 
pulled. The charge should be kept down to a small amount of Red 
Cross Farm Powder. 



iAM^ 


Mi 


kk^M 


iL 


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(.IF.Kl'.KAL \IIAV OF lU ASTICO STU.MI' IT-t.VG.MENTS ON LIGHT CLK.MUNG 

46 



(b.) A hole can be bored into the thick part of the stump near the 
original ground line (Fig. 25). 



FIG. 25. LOCATION OF A HOLE BORED 
INTO A PULLED STUMP FOR SPLIT- 
TING. SOME PREFER TO BORE SUCH 
A HOLE IN THE SAME DIRECTION AS 
THE NATURAL HOLLOW (FIG. 24) 




(c.) A hole may be punched through the mass of earth, on the 
bottom of the stump, to the forks of the main roots (Fig. 26). 




FIG. 26. PUNCHING A HOLE FOR A SPLITTING CHARGE THROUGH THE EARTH 
CLINGING TO THE ROOTS OF A STUMP. "A," LOCATION OF BORE HOLE; 
"B," LOADING THE CHARGE 



Red Cross Farm Powder is recommended for all three methods. 
Good tamping is essential to success. (See pages 27 and 28 for meth- 
ods of loading.) 

DISPOSAL OF STUMP FRAGMENTS 
Land is not cleared whe-n the stumps are simply out of the ground, 
for they are frequently more in the way when lying on the ground than 
they were when in the ground. All blasting tends to split stumps into 
fragments that can be more easily handled. If the stump wood is of 
value for fuel, or for distillation, it should be saved and hauled to 
market as soon as possible. Small fragments are naturally much easier 
to handle. Stone boats or sleds can frequently be used for short hauls 
and are easy to load and unload. For longer hauls wagons are better. 
Wagons can be loaded with the pilers shown in Figs. 27 and 28. 

47 



In many localities stump wood is simply waste, as there is no mar- 
ket for it either for fuel or for distillation. In such cases the easiest 
and quickest method of burning is to be desired. There are many 
methods of piling for burning. Each method has its advantages under 
peculiar circumstances. The selection of method should be made in 
accordance with the individual needs. 

Building Small Piles. — On small stumping jobs, especially where 
there is a considerable amount of trash to be burned, the building of 
small piles, including only two or three stumps, is found very satisfac- 
tory. The largest stump fragments can be used for the base of the pile, 
and the smaller fragments piled on top by hand, or by means of teams 
or pullers. 

Building Large Piles. — Frequently, especially on extensive clearing 
jobs, it is better to build large piles. When it is necessary to leave the 
stumps for some time to allow them to dry out, this is an excellent 
method. Some claim that the stumps burn much better when piled in 
this way. 

The "mast," or "gin pole," is most largely used in the West, where 
it gives excellent satisfaction. It is used in connection with the donkey 
engine, but it can also be used to good advantage with heavy teams. 
The pole may be erected and secured by means of guy wires or ropes, 
or a standing tree can be used to good advantage. The pole is burned 
with the pile. A good idea of this method can be obtained from Fig. 
27, page 48. 

There are a number of patented as well as home-made "boom pilers" 
that prove very satisfactory. Some of these are quite heavy and hard 
to move, while others are lighter and can be easily pulled about the field. 
One of the simplest of these is the "Conrath Filer," which is shown in 
detail in the accompanying cuts. This outfit, which is not patented, can 
be built on the farm at a cost of about $25 to $30. This outfit can also 
be used for loading wood or stump fragments on a wagon. The fol- 
lowing bill of material will assist in building the piler. The timbers 
can be of sawn lumber, but round poles, cut in the woods, are more gen- 
erally used, as they are cheaper and just as good. 

The use of a piler on large operations is almost imperative in order 
to clean up the scattered fragments and debris, so that a free space can 
be had in which to work, especially when teams and pullers are used. 

It also allows the free cleared ground between the piles to be 
plowed and worked while waiting for the piles to dry out sufficiently to 
be burned. 



48 




FIG. 27. SHOWING PILIXG STUMP FRAGMENTS BY ME.\NS OF A GIN 
POLF,. A IIEA\'Y TEAM CAN BE USED IN PL.\CE OF THE DONKEY 
ENGINE FOR LIGHT WORK 



BILL OF MATERIAL FOR CONRATII TILER (See Fig. 28) 

(a) 2 skids, 8 x 8, 20 ft. long. 

(b) 1 cross beam n-here boom sets on, 7x8,9 ft. long. 

(c) 2 cross beams for ends of skids, 5 x 5, 9 ft. 

(d) 2 standards for A frame, 5x5, U ft. 
{e) 2 brace poles for A frame, 4x4, 18 ft. 
(/) 1 pole for swinging boom, 7 x 7, 22 ft. 
(g) 110 ft. H-in. steel cable. 

(h) 40 ft. }4-m. steel cable for holding boom. 

(!) 2 25-ft. pieces yi-in. guy cable. 

(_;■) 1 shive fastened in end of boom, 34 x 6. 

{k) 2 steel blocks for piling cable. 

(0 2 double wooden pulleys for Ss-in. rope. 

(m) 2 single wooden pulleys for rs-in. rope. 

in) 2 strips of iron J^ x IK. 18 in- ''"^ng. to fasten A frame to skids. 

(0) 1 plate of iron 'i x 4 in., 12 in. (plate on cross piece at bottom of boom). 

ip) 1 piece of iron y2 x 2>2, 24 in. long, to fasten bottom of boom to cross beam, 
(gj 1 bolt for bottom of boom to swing on, 1 in. x 4 in. 
(r) 4 bolts ^ X 12 in. long. 
{s) 2 bolts 5^ X 14 in. long. 

(1) 2 bolts H X 8 in. long. 
(«) 4 bolts ^-i X 8 in. long, 
(ii) 1 bolt 1 X 9 in. long. 

fa') 1 bolt X X 20 in. long, threaded on both ends. 

(x) 4 bolts >^ X 8 in. long. 

(v) 2 bolts J^ X 9 in. long. 

(z) 2 single blocks for j6'-in. rope, for changing elevation of boom, 
(as) 2 single blocks for yi-in. cable for boom. 

49 




FIG. 28. DETAIL SKETCH SHOWIXG CONSTRUCTION OF THE COXR.ATH FILER 
(See page 4.S for Bill of Material. See Fig. 29 for photograph of finished piler.) 




FIl.;. J9. SHOWING .^ CUMI'LETE CuNK.MIl ITLER LUILT OF POLES 

50 



THE STUMP TURPENTINE INDUSTRY 
What It Means to Owners of Cut-Over Long Leaf Pine Lands 

The manufacture of turpentine and rosin is a very important 
industry in seven of our Southern States. In 1909 there were 1,585 
establishments engaged in manufacturing these products. The capital 
invested in the business was $12,375,000 and 41,959 officials and work- 
men were employed in the industr\-. 

The supply of gum is becoming exhausted, so both turpentine and 
rosin are now being extracted from the wood. 

Although it is a well-known fact that the stump contains a larger 
amount of turpentine, rosin, tar, wood oil and creosote than is con- 
tained in the trunk and branches of the tree, only the trunk and 
branches have been utilized by many manufacturers due to the exces- 
sive cost of getting the stumps out of the ground and breaking them 
into fragments suitable for retorts and "hogs." The use of improved 
hand augers and power boring machines and Red Cross Farm Powder 
has overcome these difficulties and thousands of cords of wood are 
now being blasted for the distilling plants. 

Some of the stumps are blasted from land controlled by the dis- 
tilling companies, some are blasted under contract, and some by farm 
landowners who are making the funds derived from the sale of the 
fat wood pay the entire clearing cost and are, bv a little plowing and 
work, getting their fields cleared at no actual outlay. 




FIG. 30. TWO MEN OPER,'\TING AN ELECTRIC BORING HEAD 

5i 



The stump turpentine industry offers an excellent opportunity to 
all owners of Long Leaf Pine Stump Lands. 

Methods of Blasting Pine Stumps for Distillation 

The methods used for blasting the stumps are exactly the same as 
arc shown in Figs. 15 and 16, page 35. Red Cross Farm Powder is 
recommended on account of its low cost. Its strength and velocity make 
it admirabl}- adapted for this blasting. 

Power Borers. — The only power borer now extensively used in 
the stump turpentine industry is driven b_\' electricity. A small dynamo 
and gasoline engine are mounted on a one-horse wagon. This is driven 
into the stump lands and supplies the current for driving one or two 
boring heads (Fig. 31). (Jne boring head usually bores from 300 to 
350 stumps per da\'. ( See Fig. 16, page 35, for the location of the 
hole.) 




FIG. 31. PORT.\BLE r,F,NF-:R.\TOR FOR .SUPPI.VlXd CURREXT FOR 
RUNNIXG .\K ELECTRIC r,(3RIXC, IIE.M) 



52 



Boulder Blasting 



Field boulders, whether loose rocks or solid ledges, present the 
same obstacles to cultivation as do stumps. (See again the drawing and 
remarks on page 33.) Their removal is just as necessary as is the 
removal of stumps. By a judicious use of explosives all classes of 
boulders and ledges can be successfully removed. 



METHODS OF BLASTING BOULDERS 

There are three distinct methods of loading for breaking field 
boulders. These are : "Blockholing," "Snakeholing" and "Mudcap- 
ping." Blockholing requires the smallest amount of explosives, but 
the most labor ; while mudcapping requires the smallest amount of 
labor, but a considerably larger amount of explosives ; snakeholing is 
intermediate in both labor and amount of explosives required. Each 
method has its special use as is pointed out in the following paragraphs. 

Blockholing. — Blockholing consists of drilling a hole into the 
boulder and charging it with a small amount of dynamite. It is the best 
method for breaking very hard or very large boulders, especially those 
of the "nigger-head" type that are so difficult to break by other methods. 



FIG, 32. PROPERLY PLACED BLOCK- 
HOLE BLAST. NOTE LOCATION OF 
EXPLOSIVE AND BLASTING CAP. 
TIGHT TAMPING IS ESSENTIAL 





FIG. 33. CORRECT METHOD OF LOAD- 
ING TO BLAST AN OUT-CROPPING 
LEDGE. IT IS USUALLY BEST TO RE- 
MOVE THE BURDEN OF EARTH. FOR 
LONG LEDGES, ELECTRIC FIRING IS 
I;F.„T 



The hole should usually be drilled about half way through the boulder 
and may be an inch or larger in diameter. 

When the drill hole is smaller than the diameter of the dynamite 
cartridge the explosive should be removed from the shell and packed 
firmly into the bottom of the hole. When the entire charge is in, make 
a hole for the cap in the top of the powder with' a pointed hardwood 
stick. Press the cap into the hole and tamp it in with moist soil. The 
hole should be tamped full. 



S3 



When the drill hole is large enough to receive the cartridges, it is 
not necessary to remove the paper shell. For- very large holes the 
cartridge shell should be slit several times from end to end. 

As the confinement is perfect in such loading any of the Du Pont 
high explosives recommended in this book will give good results. Red 
Cross Farm Powder and the different stumping powders are especially 
recommended. 

Blockholing is very effective in blasting out-cropping ledge's that 
are too large to remove entirely. 

See pages 22 to 26 for Methods of Making Primers, and pages 
27 to 29 for Methods of Loading and Firing. 

Snakeholing. — Snakeholing consists of punching a hole under, but 
immediately against the bottom of a boulder and placing the charge of 
explosives in as compact shape as the size of the hole will permit. A 
better idea of the method can be had by glancing at Fig. 34. The 
explosive being confined on the underside by the earth, can exert a 
powerful blow on the boulder and will roll it out, or if a sufficient charge 
is used will break it in fragments. 

This is one of the easiest and most successful methods of boulder 
blasting. The best explosives for this work are either Red Cross 
Stumping Powder or Red Cross Extra 40 per cent. Dynamite. Electric 
blasting is not generally used unless the boulders are very large and 
more than one charge is used to blow them out. Many blasters prefer 
to lift boulders out with a snakehole shot and later break them with a 
mudcap. 

Sometimes a mudcap is used on the top of a boulder in connection 
with a snakehole blast under it. Both charges are fired electrically. 
This method applies to large boulders only. 




FIG. 34. CORRECTLY PLACED CHARGE 
FOR A SNAKEHOLE BLAST. THE 
CHARGE SHOULD BE IN CONTACT 
WITH THE BOTTOM OF THE BOULDER 



9////// 

TAMPIN& / 

BLASTINCI CAP / 

CARTRIDGE / 

^ SLIT C/KRTFIIDaEs/, 

^^ PRESSED TIGHT // 

/////////////// 

See pages 22 to 26 for Methods of Making Primers, and pages 
27 to 29 for Methods of Loading and Tamping. 

Mudcapping. — Mudcapping is known by a variety of fantastic and 
expressive names, such as "Bulldozing," "Bhstering," "Poulticing" and 
"Adobe Shooting," and is made possible by the fast, shattering action 
of the higher grades of dynamite. In practice it consists of removing 
the dynamite from the shell and packing it in a compact conical heap 

54 



on the boulder, and after inserting a cap and fuse covering it with 
several Inches of thick, heavy mud. 

The explosive should be placed on the boulder at the place where 
it would be struck with a hammer were it small enough to break in 
that way (Fig. 35). This may be on the top or side. If the boulder is 
embedded in the ground, a snakehole shot to roll it out on the surface 
should first be made, because the confining dirt makes it much harder to 
break with a mudcap shot. The mud covering should be as thick and 
heavy as it is convenient to make it, not less than 5 or 6 inches, and 
should be free from stones, as the blast will throw them as though they 
were bullets. Never lay a stone on top of the mud for the same reason. 

The explosives used are Red Cross Extra 40 per cent, for easily 
broken rock, and Du Pont Straight 50 per cent, for hard nigger- 
head boulders. 



BLASTING- CAP 



MUD- 
DYNAMITE 



FIG. 35. A WELL-LOCATED MUDCAP. 
THE COVERING OF MUD SHOULD BE 
AT LEAST 6 INCHES DEEP AND FREE 
FROM STONES 




v> 



Seam Blasting. — Frequently ledges and boulders have seartls from 
which the mud or stone chips can be removed to a considerable depth. 
When such a seam is as much as one-half inch wide, successfiil blasts 
can be made by packing a reasonable amount of 40 per cent, or stronger 
dynamite into the crack and tamping it securely with moist clay. This 
method will require about the same amount of dynamite as snakeholing, 
but is more satisfactory for badly-seamed boulders or ledges. The 
greatest care must be exercised in placing and tamping the charge to 
prevent the expanding gases from escaping through the cracks. 

AMOUNT OF EXPLOSIVES REQUIRED FOR BLASTING BOULDERS 

On account of the differences in hardness of rock in different 
places, and the variations in shape in a single field, it is impossible to 
give exact information as to the amount of explosive to use. The 
following table, which is based on stone of average hardness loaded 
with Du Pont Straight 50 per cent. Dynamite, will give some idea of 
the amounts to use in making test shots. It will be necessary to vary 
these amounts on account of the great variation in the hardness of 
stone. The recommendations are valuable only for making the first 
trial shots. After these are made the blaster should be governed by the 
results obtained. 

55 





NUMTII 


K OF Cartridges Requir]i;d 


ill I'V-i-t 


Mudcapping 


Snakeholing 


Blockholing 


2 
3 
4 

5 


2 
3 

4 
Don't attempt 
Don't attempt 


' 1 
1 
IK 

4 
6 


1 



This is based on the use of Du Pont Straight Dynamite of 50 per 
cent, strength. If Red Cross Extra 40 per cent. Dynamite is used, 
increase the amounts by half, and if Red Cross Farm Powder is used 
for snakehoHng or blockhohng, dotible the amounts. 

EXPLOSIVES FOR BOULDER BLASTING 

For boulder and other rock blasting, the recommendations in this 
book can be followed literally, because the grades of dynamite recom- 
mended can be obtained in West Coast States. 

DISPOSAL OF BOULDER FRAGMENTS 

The accompanying cut shows a beautiful home built of frag- 
ments of field stones by a progressive blaster who was clearing up a 
large field. Other uses are for building fotnidations, walls, fences, 
roads, for making concrete, for filling gullies or discarded ditches 
and fo'rming blind drains to remove excesses of rainwater. 

Where large boulders leave deep holes nuich of the debris can be 
buried in the bottom of the holes, but care must be taken to keep it well 
below plow depth. 




I It (List; liuii/r (u iR\(,MiMs 01 ill n I 

I'KOM .•\tJJOI^]^(, I'lKLIl 

56 



• 1 Rs HI \S1 1 L) 



Vertical Farming 

(Deep Tillage) 



For satisfactory crop production the soils should be well drained, 
well aerated or ventilated, and well cultivated to a depth of several 
feet. 

The chief troubles to be overcome in making soils conform to 
these specifications are hardpan, tight clay and poorly drained subsoilsi 
Such subsoils 

Prevent the downward movement of water into the soil, and 
permit it to be lost by evaporation, or worse, by surface runoff, 
which causes erosion; 

Exclude the air needed by beneficial bacteria and for the 
preparation of plant foods ; 

Seriously retard or absolutely stop the penetration of roots; 
and 

Absorb too little water for the maintenance of crops during 
the dry season. 

IMPORTANCE OF WATER STORAGE 

The greatest limiting factor in the production of crops in the 
United States is the scant supply of soil moisture during the growing 
season. This is especially true of summer crops. There is a sufficient 
rainfall in most of the general agricultural sections to increase the 
average yields to much more than double the present figures. The 
greater part of this is lost either through bad drainage or by surface 
evaporation and is never used by the plants. The first great care 
of the grower should be to store every possible drop of the rainfall 
in a well-tilled subsoil and hold it there indefinitely so that it may be 
available to nourish the crops during the summer when the rainfall 
is light and irregular, and when there is by far the greatest demand 
for water. Instead of laying up money for "a rainy day," it is "stor- 
ing water for a rainless day." 

The position and character of the impervious material in the sub- 
soil governs very largely the extent and character of the damage done 
by the faulty absorption of moisture. Over a great part of the United 
States we find a reasonably good surface soil underlain by a tight 
impervious clay to great depth. On such a soil the amount of moisture 

57 



absorbed will be governed almost entirely by the surface, as the under- 
lying material is too tight and close for the water to penetrate quickly 
to any considerable depth, and so it is lost by evaporation or by running 
off along the surface. This is illustrated in Fig. 36. The first rain 
soaks the few inches of surface to saturation, but cannot easily go 
deeper, and a very unsatisfactory as well as dangerous condition is pro- 
duced. The good fertile top soil is held practically in suspension 
awaiting only a heavier rain to carry it off down the slope, leaving only 
the tight material that was below. Even if the condition does not 
become so extreme, and there is no loss by erosion, there can be but 
little absorption and storage of moisture ; and crops will suffer. 

BLASTING TO LOOSEN TIGHT SUBSOILS 

To improve the mechanical condition of such a soil the underlying 
material should be blasted to loosen it to a depth of not less than three 
or four feet. In some cases it is better to go deeper. When such a 




FIG. 36. FOR DEEP, TIGHT CLAY, THE 
BLASTS SHOULD BE NOT LESS THAN 
3 FEET DEEP. THE BLASTING 
SHOULD BE DONE WHEN THE SUB- 
SOIL IS DRY 



treatment is given, the movement of moisture is at once affected. In- 
stead of being checked at the bottom of the plowed furrow it penetrates 
immediately into thfe subsoil where it can spread out at will and where 
it will be absorbed and later used to supply the needs of the growing 
crop. 

This work should be undertaken toward the close of the dry sea- 
son, July to October preferably, when the subsoil is usually in the 
very best condition for shattering. It will then absorb the heavy win- 
ter rains and snows and hold them for future use. Impervious clay 
is usually plastic or sticky, and if blasted when wet will not be benefited 
and may even become more objectionable than before. \Mien dry it 
shatters and pulverizes well and is converted into a cracked, porous 
mass that will permit the circulation of both air and water, and the deep 
downward growth of roots. It is in this cracked condition that it 
absorbs the maximum amount of water and produces the heaviest crops. 

When sticky clay subsoils are blasted when wet, the effect is to 
produce or spring a cavity at the bottom of the blast and thus compact 
rather than loosen the soil. No general subsoil blasting should be done 
when the surface is frozen. 

58 



One Blasting Suffices for Several Years.— The duration of the bene- 
fits thus obtained is not as yet clearly worked out, but it appears from 
tests that they should be effective for a cpnsiderable number of years. 
So far they have been more marked during the second and third years 
after blasting than during the first. If proper attention is given to the 
surface it is quite likely that they will not return to their former 
state within the life of man. When heavy, deep-rooted crops such as 
alfalfa, for instance, are used to supply humus and increase the supply 
of nitrogen, the deep roots left to decay in the soil will guarantee the 
permanency of the benefits. 

Grow Seep-Rooted Crops. — The growing of deep-rooted crops fol- 
lowing subsoil blasting cannot be recommended too highly. The decay- 
ing roots leave humus down deep in the soil and subsoil. This keeps the 
-soil open and assists in creating an ideal reservoir for the storage of 
moisture. 

Lime Valuable. — On sour, wet land, where the clay is very sticky, 
• it will be found an excellent practice to use considerable amounts of 
lime in order to sweeten the soil and to assist in the formation of an 
ideal crumb structure. 

HARDPAN 

Another prevalent subsoil trouble is encountered in the layers 
of hardpan so often found within two or three feet of the surface. 
These act just as do the tight clays, already described, in preventing 
the absorption of moisture and are likely to be the cause of serious 
trouble from erosion, in addition to limiting the crop-producing capacity 
of the soil. 

In blasting such a soil, to get the greatest benefits, the explosive 
must be placed in the layer of hardpan without reference to the exact 



FIG. 37. A LAYER OF HARDPAN OVER 
OPEN MATERIAL IS EASILY DE- 
STROYED BY BLASTING. THE 
CHARGES SHOULD BE PLACED IN, 
AND NOT UNDER, THE TIGHT MATE- 
RIAL 




depth of the loading. Sometimes this may be not more than two feet 
in depth, and again it may be best to go as deep as three or four 
feet. The efifect is to break up the hardpan and permit the moisture to 
move freely. This increases the amount that may be absorbed and 
permits the growing of maximum yields. The efifect on root develop- 
ment is the same as when the deep clay is blasted. 

59 




In such a soil the blasting not only makes soil out of the hardpan, 
but opens up the way to the underlying good subsoil so that it, too, may 
assist in nourishing the crop.. 

PLOW SOLE 

Plow sole (Fig. 38) may be found either in connection with the 
other impervious conditions or alone. It lies closer to the surface and 
may not extend deeper than eight or ten inches. When such a condi- 
tion is encountered the most satisfactory relief is by thorough and 
deep surface tillage. If it can be broken up by deep plowing, that is the 
best way to get after it. When this is not practicable, and the tillage 
must go deeper, a machine like the Spaulding Deep Tillage Machine 
offers the best relief, as it will not only break up the plow sole, but will 



FIG. 38. PLOW SOLE OR SHALLOW 
HARDPAN IS MOST EASILY BROKEN 
BY PLOWING TO GREATER DEPTHS. 
THIS MAY BE DONE IN CONNECTION' 
WITH BLASTING FOR PULVERIZING 
DEEPER HARDPAN 



mix it with the better aerated surface soil, and materially hasten the 
preparation of an ideal cropping soil. 

The combination of deep surface tillage and blasting becomes 
applicable when both shallow hardpan or tough plow sole are encoun- 
tered in connection with deep hardpan or tight clay. When only one 
adverse condition is encountered, the treatment selected should be the 
one applicable to the condition. 

Sometimes a soil is found where the surface and upper sub-sur- 
face are well tilled to considerable depth and the tight clay is not 
found except at a depth of several feet. Such soils lend themselves 
readily to subsoil blasting, as the great benefits o.f the naturally deep 
soil can be materially increased by creating still more open material to 
absorb more water and to give better drainage in case of torrential 
rains. Such blasting must be deeper, and heavier loading may, in some 
cases, be found advisable. 

BLASTING TO ASSIST DRAINAGE 

Aside from the benefits of explosives for shattering impervious 
subsoils as above described, this method of soil tillage finds ready 
application in shattering subsoils to assist other drainage methods that 
are not giving satisfactory results. Good drainage can be obtained only 
when the subsoil is loose and porous. The desired depth of tillage can 
be obtained by blasting. 

60 




Tile Drains. — Where tight clays and hardpan soils are found to 
function poorly, and establish drainage courses slowly, if at all, they can 
be greatly improved by shattering the subsoils between the lines of 
tile. The same is found to be true in soils that are but little affected 
by open drains, where the water is held in too large amounts over the 



FIG. 39. OFTEN HARDPAN PREVENTS 
THE DRAINAGE WATER FROM PASS- 
ING INTO TILE OR OPEN DRAINS. 
THE RELIEF IS THROUGH BLASTING, 
WHICH OPENS UP THE NEEDED 
DRAINAGE COURSES 



subsoil quite near the drains. Care, however, must be taken not to blast 
nearer than seven or eight feet to a tile drain. 

The best practice is to thoroughly blast such soils before the tile 
is laid. This prevents all danger of injuring the tile. 

***** 

It may be seen from the above paragraphs that subsoil blasting is 
advised for undesirable hardpan conditions, along logical lines. It is 
intended to open up the lower subsoil, for chemical analyses of soils 
down to a depth of twenty feet show that on the average acre 
there are tons of plant foods which become available only when roots 
can penetrate to them, or when ascending moisture brings them up 
to the roots that cannot get down. 



SOIL MAKERS 

Alfalfa and other deep-rooted plants are .called "soil makers" 
because they penetrate this compact soil, introduce humus and pro- 
vide a passageway for the descent and ascent of water which carries 
with it the soluble, fertilizing elements ; but many subsoils are so hard 
that it is practically impossible for any plant to penetrate them. 
Even when this is possible there is no use in putting such a burden 
on the plant, because whatever vitality is expended in making its own 
home beneath the surface is subtracted from the vitality of the plant 
above the surface. In other words, the plant that has to fight for its 
life beneath the soil has little energy left for fruition. 

If we make root growth easy and quick by breaking up the 
subsoil, then we make the fertilizing elements of the subsoil imme- 
diately available and save the energy of the plant for fruition. We 
also create in the subsoil a porous condition favorable to the storage 
of water at a depth that will not keep the soil cold, and yet near 

61 



enough to the roots to feed them through capillary attraction. Subsoil- 
ing also introduces air into the soil, and it is just as necessary for. the 
roots of a plant to have air as it is for a human being to breathe. 

The effect of subsoiling is to virtually change a farm from a 
six-inch layer of topsoil to a six-foot layer. 

THE USE OF LIME 

In improving and reclaiming farm lands the use of lime must 
alvi^ays be kept in mind, because it plays such an important part in the 
upbuilding processes. 

In the reduction of tight, sticky clays to a well-granulated condi- 
tion, the effect of generous applications of lime is quite noticeable, in 
that the fine, unmanageable clay particles are drawn together into 
crumbs or granules. 

Lime sweetens the sour soils and permits a better growth of the 
leguminous green manure crops so much needed to supply humus. An 
increase in humus means that the soils can be more easily drained, will 
absorb more moisture, and, best of all, will produce more crop. 

Another beneficial effect from lime is that it increases the activi- 
ties of beneficial bacteria in the soil. Many of the most helpful forms 
will not grow in a sour soil, and may be replaced by harmful forms. 

Write to your State experiment station for printed matter describ- 
ing how and when to use the different forms of lime, and begin at the 
first opportunity the needed work of sweetening and otherwise improv- 
ing the soil. 

HOW TO BLAST SUBSOILS 

In doing this work the best results are obtained by spacing bore 
holes about fifteen feet apart to a sufficient depth to permit the shatter- 
ing of the impervious material. In deep clays of uniform nature, such 
as are represented in Sections A and C of the accompanying sketch, the 
holes should be put down to a depth of about three feet. Where the 
hardpan material is similar to that in Section B the holes should be put 




B c 

FIG. 40. DIFFERENT TYPES OF HARDPAN 

62 



down a little more than half way through the hardpan. They should 
not go below the hardpan, as there is danger of the blast lifting the 
hardpan in large chunks, rather than shattering it. Where it is desir- 
able to shatter soils similar to the one represented in Section D, the 
holes should be put well down into the deep hardpan, the depth being 
governed by the depth of the open surface soil. Each hole is charged 
with one-half cartridge of 1}^ x 8 inch Red Cross Farm Powder. 
Exact advice for putting down the holes and charging them is given in 
the text and illustrations on pages 70 and 71, and directions for making 
the primer are given on pages 22 to 25. 

In some cases of hardpan like cemented gravel or hard shale, 
slight variations must be made in the method of loading. In such 
cases it will be better to materially increase the amount of explosive 
used or to use a half cartridge of Red Cross Stumping Powder or 
Red Cross Extra 40 per cent. Dynamite. 

Subsoil blasting should be done only when the subsoil is dry, 
because wet subsoils are difficult to shatter, and the tendency of the 
explosion is to create a large cavity or pothole at the base of the blast. 
This does not benefit the land. Where the soil, as in "A," has a loose 
subsoil instead of compact clay, destroy the plow sole by deep surface 
tillage and blasting will not be necessary. 

BLASTING TO CONTROL EROSION 

Millions of acres of valuable farm land are being damaged by 
erosion or washing. The use of explosives for overcoming erosion is 
proving very effective and is applicable in three ways : For subsoiling 
the entire area to increase the total moisture capacity; for subsoiHng 
along the courses of shallow washes ; and, for blasting above terraces 
to give the water held by the terrace a chance to strike downward. A 
later chapter will describe the methods of filling gulHes that have 
already been established. 

Subsoiling Above Terraces. — In many cases high terraces hold con- 
siderable amounts of water during heavy rains. This is dangerous 
because the standing water may either drown the growing crop or so 
saturate and weaken the terrace that a break is inevitable. 



FIG. 41. CORRECT LOCATION OF 
BLASTS ABOVE WASHES TO CREATE 
VERTICAL DRAINAGE TO REDUCE 
THE DANGERS OF EROSION. 




63 




Correction is by subsoiling along the lowest part above the terrace, 
as is indicated in Fig. 41. This work should be done in keeping with 
the general advice on subsoiling given on pages 57 to 65. 

Subsoiling to Stop Washes. — Subsoil blasting, slightly heavier and 
closer than is advised for general work, is effective in stopping shallow 
washes. The blasting should be started somewhat above the first 
show of the wash and should be violent enough to thoroughly shake the 
subsoil to a depth of at least 40 inches, and for at least 15 feet to each 
side of the wash, as is indicated in Fig. 42. 

FIG. 42. SHOWING THE LOCATION FOR 
SUBSOIL SHOTS ALONG A SHALLOW 
WASH. THE SHOTS ARE INDICATED 
BY CIRCLES "B." THESE SHOULD 
COMPLETELY SHAKE THE CENTER 
OF THE WASH "A" AND BE LOCATED 
ALONG THE SIDES SO THAT THE SUB- 
SOIL IS SHATTERED FOR AT LEAST 
15 FEET EACH WAY. FOR NARROW 
WASHES TWO LINES OF HOLES ARE 
SUFFICIENT 



GULLY FILLING 

When gullies are too deep to plow across, the banks or sides can be 
blown down by blasting. The loading can be in vertical holes (A, Fig. 
43), or in snake, horizontal or flat holes (B, Fig. 43). Vertical holes are 
usually best for flat banks and snake holes for steep banks. They should 
be deep enough and charged with a sufficient amount of explosives to 
shatter and throw down the bank so that the work of leveling can be 
completed with plows or drag scrapers (Fig. 78, page 103). The exact 
loading must be determined by trial shots. For a gully six feet deep a 
good trial shot would be with holes 5 to 6 feet apart and about 5 feet 
deep. They should be loaded about half full of Red Cross Farm Pow- 
der. The effects of such a blast will indicate clearly how the next holes 
should be spaced and loaded. Correct loading should throw enough soil 
over into the gully to permit the use of teams in plowing and scraping 
down the banks, and the shock of the blast will be sufficient to shatter 
the deeper subsoil, so that it will absorb an increased amount of water 
and prevent further erosion, except under very trying conditions. 

As there is sometimes danger of the freshly moved soil being washed 
away by heavy rains, a good precaution is to build an occasional dam 
of logs or boulders across the gully — to act as an anchor. Another good 
anchor is a woven wire fence stretched across the gully, having its 
top flush with the surface of the ground. A pile of cornstalks, old hay 
or brush above either type of anchor helps to guard against sloughing. 

64 



If broken boulders, stumps, logs or any other loose material is 
placed in the bottom of the gully before it is filled the effect will be 
that of a deep, well-laid tile drain. Through this the excesses of water 
will be discharged without injury to the surface. In many cases, it will 
be well to straighten up the bottoms of the gullies and lay permanent 
subdrains before the filling is commenced. 

For wide shallow gullies, where the entire surface has been lost, 
but where the cutting has not been deep, the treatment -is the same as 
deep subsoiling with the spacing of the holes decreased to ten or twelve 
feet. In filling gullies large amounts of unaerated subsoil are exposed, 
and care should be taken to add humus either in the shape of rank- 
growing green-manure crops, vegetable litter or rough manure. Old 
cornstalks, forest leaves, or mildewed straw can be used to good 
advantage. 

Specific directions for electric blasting are given on pages 31 
and 32. 



To derive the greatest benefits from gully filling, the work should 
be done in connection with subsoiling and terracing along the slopes 
ibove the gully, for in this way the water from violent rains does not 
immediately rush to the lower slopes, but is held back and absorbed by 
the loose, well broken subsoil. Hence, the newly filled gully is not in 
danger of being again cut out and eroded by a too sudden flow of a 
large volume of water. 




A B 

FIG. 43. METHODS OF LOADING TO BLAST DOWN GULLY BANKS. "A" IS BEST 
FOR SLOPING BANKS, AND "B" FOR THOSE HAVING STEEP SIDES. ELECTRIC 
FIRING IS RECOMMENDED 



65 



Blasting in the Orchard 

A Proven Proposition for Tree Planting 

In 1910 the Du Pont Powder Company began to promote the use 
of explosives in planting new orchards and rejuvenating old ones. The 
idea was not original with us. 

Nearly a quarter century ago, near La Mesa, Cal., ground was 
blasted for tree planting, because the orchardist found the work of 
planting with a spade in his hard soil too difficult. His experiment 
was a success. The trees lived, thrived and bore exceptional apple 
yields for many years. 

Other orchardists and farmers in different sections of the country 
thought of the same scheme for preparing a home for the tree roots. 
We have records of such plantings, eleven, sixteen and twenty years 
ago, before the idea really began to spread. 

After we began to advertise it extensively and sent out demon- 
strators throughout the country, many farmers and orchardists tried 
the new plan on a small scale. Now, because of the universal success 
of correct blasting for orchard planting, the majority of fruit trees are 
being planted in blasted ground. 

There remains but three classes of fruit growers who still stick to 
the old methods: 

1. Those whom we have not yet reached through our promo- 
tion efforts ; 

2. Those who have tried planting trees in blasted soil without 
knowing how to do it and hence failed to get satisfactory results, 
and 

3. The class of farmers, orchardists and horticulturists who 
decry anything that is new, or which is being promoted by a busi- 
ness concern. 

Millions of fruit, nut and shade trees and ornamental plants have 
been planted in blasted ground long enough to prove the great advan- 
tages of the method. America's leading orchardists and nurserymen 
now plant exclusively in blasted ground. 

No one can afford to plant trees by any other method except in soil 
that is loose and sandy to a depth of several feet. In such soil blast- 
ing is not advantageous except for the elimination of fungus and 
nematoid troubles. 

66 



WHAT BLASTING IN ORCHARDS ACCOMPLISHES 

1. It mellows the ground to a depth of five or six feet and through- 
out a circular area ten to twenty feet in diameter, making it easy to 
dig the hole and plant the tree correctly. 

2. It creates a porous, water-absorbing condition in the subsoil that 
makes the tree drouth-proof, stopping the big, first year loss, and 
invigorates growth. 

3. It makes root growth easy and makes tons per acre of new 
plant food available, hence speeds up the growth of the tree and makes 
it fruit one to two years earlier. 

4. It creates drainage and prevents stagnation of water on surface. 

5. In old orchards that were planted by the old methods and have 
ceased to bear well, it is of great value in rejuvenating the old trees, 
causing them to yield heavily. 

6. It destroys fungus, nematode, and other orchard soil diseases, 
hence makes it possible to plant new orchards where old ones have 
been removed without waiting several years to rest the land and get rid 
of the diseases. 

7. At a cost little or no more than of old-style planting, it causes 
at least a year's earlier return on the investment in new orchards, and 
greatly increased returns thereafter as compared with spade-set 
orchards. 

PLANTING A TREE FOR KEEPS 

In studying comparative costs of planting fruit trees, the investi- 
gator is confronted with widely varying figures and methods. 

There seems to be no machine for planting fruit trees such as a 
corn drill, but the method of some planters approximates the work of 
a machine in speed, if not in efficiency. 

They lay off the site of the proposed orchard in 20-ft. to 40-ft. 
checks, depending on the kind of trees to be planted. Cross furrows 
are plowed through the field, marking it off in squares. 

One man drives along a furrow with a wagon-load of trees, 
another lays a tree near each of the furrow intersections, and a third 
stands the tree in the intersections, kicks some soil over the roots, 
tramps it down, and moves on to the next intersection. This method 
expresses a touching confidence in Nature, but results indicate such 
confidence is misplaced. " 

A tree that survives such treatment must have as many lives as the 
proverbial cat, and if it lives, how many years must elapse before it 
bears any fruit ? What grade of fruit can be expected from a tree aged 
and bent with the fight for existence before it saves strength enough 
to bear at all ? 

67 



Going to the other extreme we find a horticulturist advising : "For- 
get you are about to plant a tree and imagine you are going to bury 
a horse and dig a hole accordingly. Remember you can plant it only 
once, and its health and growth, the age at which it begins to bear, and 
the quantity and quality of fruit borne, depend chiefly on the care and 
thoroughness used in planting it." 

Up to a few years ago, the method followed by most good or- 
chardists was to dig a hole seldom as much as 2 feet in diameter and 
18 inches deep, then plant the tree in top soil or a mixture of top soil and 
subsoil. Under this system the loss the first year ran from 25 per cent, 
to SO per cent., depending on soil and weather conditions. 

Then tree planting with explosives was taken up by a few orchard- 
ists who realized the shortcomings of the ordinary methods, and the 
necessity of cutting down first year losses, and speeding fruition. 

The first objections to the new method were largely financial. The 
cost of explosives, blasting cap, fuse and labor ran from 8c. to 15c. per 
hole, whereas trees could be planted with a spade for 3c. to 5c. per 
hole. The trouble with this comparison is that the work performed is 
not the same, hence costs should not be compared. 

The question involved is, how soon does the planter want a return 
from his investment and how large a return? The only way to com- 
pare costs is to consider the profit sought and which is the cheaper way 
to get it. 

In the first place, the purpose of blasting is not to supplant the 
spade. It is possible to dig the hole with explosives, just as a hole 
may be excavated for a fence post. But the real object of blasting is to 
mellow the subsoil and make root growth and spade digging easy. 

The orchardist must take into account the fact that by loosening 
the subsoil in a thorough manner, the moisture from the rains can soak 
in quickly, not only immediately around the spaded out hole, but the 
fine cracks radiating in all directions form passageways for the further 
absorption of water. They carry the life-giving moisture to great 
depths and store it there, to be brought out again by capillarity during 
the dry seasons for the sustenance of the tree. Our records show that 
the yearly saving in replacement and replanting costs in young orchards 
more than balance any expenditure for explosives. 



68 



HOW TO DO THE WORK 

Laying Out the Orchard.— The places to set the trees or other plants 
are selected and marked by a stake, or better, if the field is large, by 
furrows plowed to indicate the exact lines for the trees, and crossed at 
the proper intervals by other furrows to indicate the spacing in the 
rows. Sometimes a heavy cord or light wire stretched across the field 
will materially assist in laying out the orchard. 

When to Blast. — Blasting for tree planting is best done in the late 
summer because it is easier to catch the subsoil in a dry condition, but 
blasting in the spring for spring planting, although the subsoil is apt 
to be wet or damp, is nevertheless much better than planting in dug 
holes. It should be done as many days ahead of planting as possible, 
to get the effect of air and sunlight in the hole. 

Examine the Soil. — The exact nature and depth of the subsoil 
should be known in order that the explosive may be used to the very 
best advantage. The only way to know this is to go down and see. Do 
not stop at the surface but go down four or more feet. Using a good 
soil auger is the best and easiest way to test out a subsoil, but if one 
cannot be had, dig a hole. Another way is to blast out a test hole 
and examine each layer of the soil. This is not so good as the other 
methods as the blast so disturbs the subsoil that it is hard to tell just 
what the original condition was. 

How Deep to Blast. — There are many dififerent kinds of subsoil, 
but those illustrated by the drawings are the most common. If the 
arrangement of the soil is like that in illustration "A," Fig. 44, place 
the explosive well down into the clay and destroy any shallow plow sole 
with a good plow. The best depth for blasting in such soil is usually 
from thirty to thirty-six inches. 




FIG. 44. 



A B C D 

DIFFERENT TYPES OF HARDPAN ENCOUNTERED IN THE ORCHARD 



In soils like the one represented in "B," Fig. 44, place the charge 
toward the bottom of the hardpan so that the entire layer may be pul- 
verized, but do not go below the bottom of it, as the force of the blast 
will tend to raise the hardpan in chunks rather than shatter it. The 
depth is governed absolutely by the depth of the hardpan. 

69 



Illustration "C," Fig. 44, shows one of the most common subsoil 
troubles. This type of hardpan or tight clay is usually too deep to blast 
through and relief is obtained by pulverizing several feet of the top, 
which if well done will be found to be sufficient to store moisture and 
furnish room for an ample root development. For such a condition the 
blast should be made not less than three feet deep. 

Occasionally a soil is found like that shown in "D," Fig. 44, which 
will usually be found to require deeper blasting. The explosive should 
be placed well down in the hardpan — the deeper the better. 

When very deep loading is practiced it is best to increase the 
amount of the charge, sometimes to more than double the amount nor- 
mally use'd. 

Making Bor.e Holes. — A number of different methods have been 
devised for making the bore holes for loading, but so far no other tool 
has given such good results as a heavy subsoil punch (Fig. 45). This 



FIG. 45. PUNCH FOR MAKING THE BORE HOLES. THIS IS DRIVEN 
WITH A HEAVY HAMMER (See page 19) 

tool is made of Ij^-inch steel and should be not less than three feet long. 
Smaller drills will not be satisfactory, as the explosive cartridge is 
itself 1% inches in diameter and when primed with cap and fuse is 
difficult to load into a smaller hole. The punch is driven to the desired 
depth (Fig. 46) with a sledge, and loosened by pounding on the sides, 
after which it can easily be withdrawn. 

A soil auger is quite satisfactory for making a small number of 
holes, but is too slow and expensive if there is much work to be done. 
However, for holes deeper than three feet, one can be used very satis- 
factorily to deepen the drilled holes. In some cases holes can be made 
with a heavy crowbar. Some soils are so hard, being in reality soft 
rock, that a rock drill is required to make the holes. 






Ki 






FIG. 46. PUNCHING THE HOLE 



FIG. 47. THE CHARGE IN PLACE 



Preparing the Charge,— The charge is prepared by cutting off a 
piece of fuse as long as the hole is deep, and crimping a cap on one end 

70 



by means of a cap crimper. The cap with the fuse attached is inserted 
into the explosive used, and securely tied. (See pages 22 to 25 for 
Methods of Making Primers.) 

Loading the Hole. — Start the charge into the bore hole and press 
it gently to the bottom with a wooden tamping stick (Fig. 47). Pour 
in four or five inches of loose dirt and tamp it gently (Fig. 48), then 
pour in more dirt, preferably slightly moist as it packs better, and tamp 
firmly (Fig. 49). When the explosive is covered with several inches 
of lightly packed soil the rest of the tamping should be made as hard 
and tight as is possible, using the stick in one hand. The hole should be 
tamped full. 



-uGMrrAMPiNs 
-atA^r »6 CMP 



^'-'^MMSS^iR 



-■//(j«'>>/^<f<A;^''y;;.^:-:^^^^ 



ii 






FIG. 48. LIGHT TAMPING OVER 
CHARGE 



FIG. 49. TOP OF HOLE TAMPED 
TIGHT 



Firing the Blast. — The next operation is to light the fuse and re- 
tire to a sufficient distance to avoid any loose material that may be 
thrown out. If the loading is properly done and at a sufficient depth 
there is usually only a thud and a cracking at the surface and no soil 
is thrown into the air. 

How to Treat Blasted Holes. — If the holes are blasted in advance 
of the time of setting the trees they are left without further attention 



\. 



"V^ ~l 



» A » 






•y 



FIG. 50. THE BLAST THOROUGHLY 
CRACKS THE SOIL, BUT LEAVES A 
CAVITY OR POTHOLE AT THE BOT- 
TOM. THIS MUST BE FILLED 






until planting time, unless it is desirable to add some manure or fer- 
tilizer to be dififused through the soil. This is a good practice, espe- 
cially on poor soil. If the soil is sour, sticky clay, a few pounds of lime 
scattered in the hole will materially assist in loosening the clay and 
keeping it permanently granulated and sweet. 

71 



Setting the Tree.— When the trees are to be planted shovel out the 
hole and locate the cavity that is usually sprung at the bottom of the 
hole (Fig. 51). Fill this with tamped soil to firm the base to prevent 
subsequent settling of the tree. The filling should be up to the level it is 



FIG. 51. THE BEST PRACTICE IS TO 
SHOVEL OUT THE LOOSE SOIL AND 
EXPOSE THE POTHOLE. THIS IS 
EASILY DONE IN THE FRESHLY 
BLASTED HOLES 




l-rVT,.! 



<(9^'>^'r 



desired to set the tree, taking care to keep the soil well tamped. Set the 
tree with the roots in as near their original position as possible and pack 
them with the top soil that. has been shoveled out of the hole (Fig. 52). 

When no attention is paid to settling or firming the soil in the bot- 
tom of the hole, trouble often results from the tree settling too deep 
after the first heavy rains, but this trouble has never been observed 
when the holes were properly examined and the described precautions 
observed in setting the tree. 

Just before packing the soil around the trees be sure that they are 
in line with the rest of the row. 

When trees are set as much as thirty or more feet apart it is 
an excellent practice to place blasts midway between the rows after the 
trees have been growing several years. These will open up the subsoil 
between the trees that was but slightly disturbed by the original blasts 



\l 



FIG. 52. AS MUCH OF THE HOLE AS 
POSSIBLE SHOULD BE FILLED WITH 
FERTILE SURFACE SOIL; THE REST 
CAN BE FILLED WITH THE SUBSOIL 
THAT HAS BEEN DUG OUT. THIS 
SHOULD BE WELL PACKED TO PRE- 
VENT SETTLING. THE TREE IS SET 
WITH THE ROOTS SPREAD OUT IN 
THEIR NATURAL POSITION 



and will induce more vigorous root growth, and consequently better 
trees will be the result. 



72 



It should be remembered that this method of resetting apphes not 
only to orchard trees such as the apple and peach, but to nut trees, 
shade trees, berries, vines, roses and all classes of ornamental and com- 
mercial trees and shrubs, and is proving a money-saver as well as a 
money-maker. 

For blasting holes to set large trees additional benefit is derived 
by placing several blasts close together so that the subsoil is more 
thoroughly shattered. 

Explosives Recommended. — The explosives recommended for tree 
planting are Red Cross Farm Powder for all sections east of the Pacific 
Coast States and either Du Pont or Repauno Stumping Powder on the 
Pacific Coast. 

Usually one-half cartridge charges are sufficient, except in the 
heaviest hardpan and where loading deeper than 40 inches is required. 




H 




[«^#>^w. 


/w 




P ^m 


?"•?. r , "- »•,' p- 


^^m 


:C''¥«j^^!^| 


^^■^^S^ 


'"^*'9'"': 


"'■y'' v-'^^%^'- ,'*;,. 



UNBLASTED HOLE 



BLASTED MOLE 



73 



RESULTS SHOW ABOVE AND BELOW GROUND 





Trees "A" and 
"C" were planted 
in blasted holes. 

Trees "B" and 
"D" were planted 
in unblasted holes. 

All trees are the 
same age. 

Even if the fruit 
from trees planted 
in blasted ground 
were not superior 
in size, color and 
flavor, the financial 
advantage derived 
from the earlier 
maturity of the 
trees should cause 
every orchardist to 
adopt the blasting 
method except 
those having a deep 
soil, mellow to a 
depth of five to six 
feet, in which case 
blasting will be of 
no benefit, except 
to destroy nema- 
tode and perhaps 
other root pests. 





74 



TREE REJUVENATION 

Cultivating Old Pruit Trees, Shade Trees, Vines and Bush 
Fruits by Blasting 

The object of blasting around old trees and vines is to open up 
the subsoil so that the roots may spread farther and go deeper, to 
increase the amount of plant food available for the roots, to establish 
better drainage and to increase the water-holding capacity of the soils. 
Blasting around root-bound trees or in resistant subsoils is strongly 
advised. The actual blasting is similar to the blasting for subsoiling 
and tree planting. 




For Small Tree 



For Large Tree 



FIG. 53. LOCATION OF CHARGES FOR REJUVENATING TREES 

Ordinarily it is better to blast on one or two sides of a tree the 
first year and blast on the remaining sides one or two years later. 
The blasts should be placed not closer than six feet to small trees, and 
should be slightly beyond the spread of the branches for large trees. 



'^wil,. 



FIG. 54. CRATERS SHOULD BE BLASTED 
IN POOR SOILS. THEY ARE FILLED 
WITH ALTERNATE LAYERS OF SOIL 
AND MANURE OR WITH SOIL MIXED 
WITH CHEMICAL FERTILIZERS 




Where the subsoils are deficient in plant food or humus, excellent 
results are obtained by putting down holes a few feet beyond the spread 
of the branches to a depth of about four feet and loading them with a 
sufficient amount of explosives to blow out a hole. This should then 

75 



be filled with alternate layers of manure and soil, or with a mixture 
of manure and a suitable fertilizer (Fig. 54). 

Where trees tend to develop a strong tap root, but are stunted by 
a stratum of hardpan lying immediately under them (Fig. 55), relief 
can be had by starting a hole two or three feet away from the trunk 
and driving it diagonally under the tree into the hard material. Unless 
this hole is three or more feet deep the charge should not exceed one- 
third of a cartridge of Red Cross Farm Powder and not over one- 
half a cartridge if deeper. Great care must be exercised in this method 
of loading, not to loosen or blow out the tree. Except in extreme 
cases, loading to the side is better. Blasting the hardpan between the 
trees should be done at the same time as that under them. 



B 




FIG. 55. THE CORRECT LOCATION 
OF A LIGHT CHARGE OF EX- 
PLOSn'E FOR B R E .\ K I K G 
THROUGH HARDPAN THAT IS 
DWARFING THE DEVELOPMENT 
OF A TAP ROOT. THE WORK 
MUST BE CAREFULLY DONE, 
AND THE CHARGE VERY LIGHT 



When blasting around or under growing trees materially prunes 
the roots, the tops should be cut back to temporarily reduce transpira- 
tion to correspond with the reduced ability of the roots to obtain a suf- 
ficient amount of moisture. The roots will then put on vigorous growth 
and absorb increased amounts of plant food and moisture to nourish 
an increased growth of top, and, in case of fruit trees, an increased 
production of fruit will result. 

(See pages 27 to 29 for methods of loading and firing.) 




RESULT OF SUCCESSFUL I'.LASTING IN 1S<)7 

76 



Land Drainage 



The drainage of the wet lands of American farms is more impor- 
tant and will develop greater wealth than would be possible by oper- 
ating all the gold mines in the 48 States and Alaska. There are more 
than 75,000,0CX) acres of swamp and overflowed lands, and more than 
100,000,000 acres need better drainage to bring them up to a satis- 
factory crop-producing condition. 

The extent of the individual drainage proposition varies from a 
few square rods in the corner of the farm to tracts of several millions 
of acres. Practically every farm in the heavy crop-producing areas of 
the United States needs some ditching, and there is hardly a stream in 
the entire boundary of the Union that does not need to be corrected to 
give better service in discharging the large amounts of waste water 
from heavy rains, and to protect low lands. 

Drainage does not simply mean getting the standing water off of 
the surface of the fields. It must include the lowering of the water 
table in the soil to a sufficient depth to allow the natural changes in the 
subsoil to take place without a check, and to permit the deep-rooting 
of plants. Neither is possible if the soil and subsoil are choked with 
water. Drainage performs the double purpose of storing the greatest 
amount of available soil moisture and disposing of all excesses. 

The mosquito pests and the attending diseases are the result of 
poor drainage, which renders parts of the country almost uninhabitable. 
Relief in this particular alone will amount to an increase in land values 
to several times the present selling price. 

Good roads are essential in any prosperous community, but can- 
not be maintained without good drainage, as wet roadbeds, no matter 
what the surface may be, will never stand traffic. In many cases the 
processes of ditching and road building are carried on hand in hand 
with the greatest success. 

■Drainage includes everything from deep cultivation to permit the 
subsoils to absorb the maximum amount of water and hold it out of the 
drains, to the digging of ditches more than a hundred yards in width, 
and many feet deep. 

77 



METHODS OF DIGGING DITCHES 

The oldest and best-known method of digging ditches is with the 
pick and shovel, which requires much hand labor and is usually very 
expensive. Where very narrow ditches are needed, as for the laying of 
underground tile or pipes, where the ditches will later be filled with 
the dirt that has been dug out, either hand or mechanical diggers are 
used, though both methods are greatly impeded by wet soils, roots, and 
stumps. 

For large, long ditches the floating dredge, drag-line excavator, or 
other heavy digging machinery finds unquestioned use, in connection 
with explosives for stumping and loosening heavily impacted soils and 
rock. 

The newest method of ditching, and one that is growing in use on 
account of its speed and economy, is blasting. By this means ditches 
from 2 to 6 feet in depth and from 4 to 15 feet in width can be exca- 
vated most satisfactorily in every type of material except loose, dry 
sand. The adoption of this method of ditching means a saving in 
time and money and in getting ditches where no other method is prac- 
ticable on account of the soil conditions. The method finds ready appli- 
cation in everything from clear muck or heavy cla_y, to the worst swamp 
conditions A\here roots, stumps and an excess of water render every 
other method impracticable except for very large ditches where heavy 
machinery must be used. 

No expensive equipment is needed. The outlay for explosives can 
be made for the exact amount of work that is to be done, which relieves 
the need of a heavy overhead charge for money invested in equipment 
and tools. Ditch blasting is applicable on everything from the short 
ditch to drain the back field to the correction of miles of large streams. 





Loading The Ditch 

BLASTING A DITdl TIIRilUGlI SWAMPY GROUND 



76 



The methods are simple and reliable, as will be pointed out in the 
following reports of work actually done. 

The rational use of explosives will mean a saving of millions of 
dollars in the reclamation of the large drainage districts and in the per- 
fection of drainage on individual fields. 



DITCHING COSTS 

The growing interest in drainage and canal construction is increas- 
ing the attention paid to the actual costs of digging, and the methods 
employed. The inquiries have brought out interesting and instructive 
facts, which if made use of, will result in a material saving to those 
undertaking drainage propositions. 

Ditching equipment now varies all the way from light spades to 
enormous dredges, tower excavators and explosives. The selection of 
the method of digging must be governed by the nature of the material 
through which the ditch is to be dug, the size and length of the desired 
ditch, and the comparative costs of the methods applicable to the condi- 
tion. Despite the enormous array of equipment there should be no con- 
fusion in the selection made for any specific job or class of work, as 
each method has its own peculiar characteristics that adapt it better 
than others to certain peculiar conditions. 

The practical range of the economic use of explosives in ditching 
is for open ditches ranging in size from shallow drains about four 
feet wide, up to the minimum sizes for which a floating dredge would be 
recommended, and for slightly larger ditches where the length is not 




ANOTHER BLASTED DITCH 

79 



great enough to warrant the erection of a dredge. For ditches of these 
sizes blasting is recommended in hard, dry soil ; loose and solid rock ; 
muck and swamp soils ; and, in fact, in all soils except loose sand. Its 
applicability is increased by adverse conditions, such as swamps, stumps 
and boulders that make conditions undesirable for hand or mechanical 
digging. 

The use of explosives in connection with dredging operations is 
for stumping, boulder and ledge blasting, and for loosening material too 
hard or heavy for the dredge to handle economically. In ditching for 
laying underground pipes, the use of explosives is not recommended 
for removing the earth, but is useful for loosening hard material to 
reduce the cost of the hand work. 

On account of the variability in the conditions encountered, it is 
rather difficult to give exact information with regard to cost, without 
having first made a careful examination of the soil and other condi- 
tions. The following paragraphs describe typical conditions and give 
the amount of explosives used in blasting ditches 'of the sizes mentioned 
and will be of considerable use in estimating final costs. 

In swampy ground where the soil varies from muck to wet sand 
mixed with decaying organic matter, and where the heavy swampy 
growth of trees is but freshly cut, the use of between three and three 
and one-quarter cartridges of Straight 50 per cent. Dynamite, in prop- 
agated blasts can usually be depended on to dig one yard in length 
of ditch seven to eight feet wide and something over three feet in depth. 
This is a condition that usually prevails along small overflowed streams, 
and in permanent swamps. This size of ditch is one that is proving 
very useful in correcting the streams and for sub-mains in connection 
with larger drainage channels. 

For ditches one to two feet narrower, under the same conditions 
the use of the same amount of 40 per cent. Low Freezing Dynamite 
or Gelatin, in electrically-fired blasts, will give a slight reduction in 
the cost of a running yard of ditch. 

Under the same conditions, double the amount of Straight 50 per 
cent. Dynamite loaded in two rows spaced four feet apart, and fired by 
the propagated method, ordinarily digs a ditch from three to four feet 
in depth and from twelve to fifteen feet top width. By using three 
lines of holes with the same loading for each hole, or three times the 
amount of dynamite given for the small ditch, a ditch of the same 
depth and from sixteen to eighteen feet wide can usually be obtained. 

It may be seen from these suggestions that the removal of a cubic 
yard of dirt from the larger ditches where two or three lines of holes 
are used, is slightly more expensive than from the small ditch loaded 
with one row of charges of Straight 50 per cent. Dynamite. For the 

80 



small ditches blasted with a single line of holes, it has been found that 
the least cost, when based on the lineal yard of ditch, is with the lower 
strength of dynamite, but where larger ditches are needed there is a 
material saving when the stronger grades are used. 

In digging through coarse, sandy loam in a dry section, or sand 
that is not too dry, two to two and one-quarter cartridges of 40 per 
cent. Gelatin fired electrically have in a large number of tests, excavated 
one running yard of ditch from two and one-half to three feet deep and 
from four and one-half to six feet wide. This soil condition is one of 
the hardest to blast, and the work should best be done after a period of 
rain, as the wet soil is blasted with a smaller amount of explosives, or 
else a larger ditch results from the use of the same amount. 

In clay or heavy loam soils that are sufficiently moist to ball a little, 
the loading just described will blast a slightly larger ditch. For increas- 
ing the size of either ditch two or three lines of holes are used. The 
increase in the amount of work done and the size of the ditch will be 
in about the same proportion as that described for the use of additional 
lines of holes in swamp soils. 

For digging very large ditches, as in the correction of large, 
crooked streams, the loading must conform to the work to be done, 
so that directions for loading are apt to be misleading. The work 
usually changes in character so rapidly that each blast is in reality a 
trial, and only the most careful loading should be attempted. Where 
the required width is such as has been given for swamp ditclips, but 
slightly greater depth is needed, it is obtained by loading a little deeper 
with an additional cartridge in each hole. For depths as great as 6 and 
7 feet it is usually best to make two blasts ; the first to give a depth of 
three or four feet and the second or bottom one to clean out the bottom 
of the ditch. Three lines of holes spaced four feet apart each way are 
usually best for making the first shot ; then use two lines of holes with 
the same spacing in the bottom of the excavation made by the first blast. 
The amount of explosives needed for a lineal yard of such a ditch will 
vary greatly with the soil. In easily lifted soil such a ditch will usually 
require about eight to ten cartridges per yard, while some of the more 
difficult soils to blast will require at least a half more. 

A TYPICAL EXAMPLE OF DITCH BLASTING 

While it is the intent of this book to give advice with regard to the 
use of explosives, the following report of a typical ditch blast is not 
out of place as it is so characteristic of numbers of ditches that are 
being blasted all over the country. 

An adverse condition was selected in the swamp land of Georgia 
for a demonstration of ditching with dynamite before the Georgia 

81 



Drainage Congress, at a recent' annual meeting. The soil was a sandy 
muck saturated with water, and laced together with a luxuriant 
growth of roots. The surface was studded with large green gum and 
bay stumps. The location was selected because the managers consid- 
ered it an impossible undertaking. An idea of the conditions can be 
gotten from the accompanying illustrations. 

The line of the ditch was laid off with a light cord. Holes were 
punched along this, spaced two feet apart, to a depth of thirty inches. 
Each hole was loaded with two cartridges of dynamite ; one 60 per cent. 
Du Pont Straight, the other 40 per cent. Red Cross Extra. A few 
extra cartridges were put directly under the larger stumps. The blast 
was fired by the propagated method, using only one cap to each section 
of ditch. 




LO.\DIKG THE DITCH 



The result was a clean ditch 9 feet wide and 3'/2 feet deep, with a 
bottom almost absolutely true to the desired grade, at a cost of less than 
10^2 cents the cubic yard. The minimum estimate for hand labor on 
this job was 25 cents the yard, and it is quite unlikely that the work 
could have been done at this price. 

Following this demonstration the actual ditching, on a commercial 
scale, of neighboring land, was done with d\'naniite. The results were 
entirely satisfactory. 

82 




THE FINISHED DITCH 



METHODS OF LOADING DITCH BLASTS 

Tliere are two distinct methods of blasting ditches, the propagated 
and electric. The propagated method can be used only in wet soils, 
while the electric method can be used in either wet or dry soils. The 
explosives and blasting supplies needed and the methods of loading vary 
considerably in the two methods. 

Among the most striking advantages of ditching with dynamite, 
as compared to other methods, are the reduction in cost, the absence of a 
large soil pile along the ditch, the little time required, the absence of 
overhead expenses for equipment, the ability to dig successfully where 
the conditions are too bad for other methods, the adaptability to both 
large and small ditches, and the simplicity of the methods. These 
have been pointed out. 

DITCHING IN SATUEATED SOILS WITHOUT A BLASTING 
MACHINE— PROPAGATED METHOD 

In wet soils, where holes two feet deep will stand half full of 
water, the quickest and generally the most economical method of 
ditching is with Du Pont Straight 50 per cent. Dynamite. Only a 
straight dynamite can be used for this zvork, as other grades are too 
insensitive to he detonated by the shock from a single primer in a cen- 

83 



tral hole. This can be practiced in the roughest of swamps, even where 
there are several inches of water standing on the surface or where the 
surface is covered with the heaviest of swamp stumps. 

This class of ditch blasting should not be attempted when either 
the air or water is colder than 50 degrees F. 

The simplicity of the method and the truly wonderful results 
obtained must be seen to be fully realized. 

The course of the ditch having been decided on by a survey or 
close study of the slope, as indicated by the surface drainage and the 
trees having been chopped from the right of way, the work may be 
begun. 

Test Shots. — The first thing to do is to try a few trial shots to ascer- 
tain the best depth and spacing for the holes. For ditches up to 3 or 
3^ feet deep the depth of bore holes will usually be about 24 to 30 
inches, and the spacing between holes from 18 to 24 inches, although it 
may be necessary to increase the depth and decrease the spacing in 
some cases. It is well to begin the test with holes two feet deep and 
18 inches apart. Keep these in line and load about 10 of them with 
one cartridge each. If a little water covers the cartridges in the holes 
no further tamping will be needed. If not, tamp well with earth. 
After the entire line is loaded, one hole is charged with an extra primer 
cartridge (see pages 22 to 25 for Methods of Making Primers), and it 
is also well to put one additional cartridge in each hole adjoining the 
primer. 

This loading should lift the soil at least two hundred feet into 
the air, scatter it over the adjoining swamp for a distance of 150 
feet and leave a good, clean ditch. If it does not, try a different load- 
ing. It may be necessary to make the holes deeper in some soils and 
not so deep in others. Usually in swamp soils the ditch made is a 
foot or two feet deeper than the charge, but sometimes it is necessary 
to load to the full depth. 

If the test shot makes too large a ditch, the spacing can be 
increased a little, but should seldom be greater than 24 inches, and then 
only in warm soil. For very small ditches less than a full cartridge of 
explosive may be used in each hole. 

Amount of Charge and Size of Ditch. — Small ditches (for instance, 
about two feet deep and three feet wide) in such soils, when there is 
little trouble from roots, can be 'dug with half cartridge charges, but 
when using such small loads the spacing between holes can seldom be 
over 18 inches. 

Larger ditches can be dug by using two or more cartridges in 
each hole, and a second, or even a third line of holes may be put down 
about four to five feet from the original line and loaded in the same 

84 



way. When two or three lines of holes are used it will be necessary 
to use one electric cap in each line (Fig. 56), or to put in one or two 
extra charges between the rows to insure the simultaneous detonation 
of all the charges. (Fig. 57). 




FIG. 56. SHOWING LOCATION OF TWO ELECTRIC BLASTING CAPS IN A 
PROPAGATED DITCH BLAST. THESE ARE TO INSURE BOTH LINES FIRING 
AT THE SAME TIME. IF THREE LINES ARE USED A THIRD ELECTRIC 
BLASTING CAP IS USED IN IT. THIS IS USED WHEN A BLASTING 
MACHINE IS AVAILABLE 




FIG. 57. SHOWING CORRECT METHOD OF LOCATING EXTRA CHARGES— "B" 
TO CARRY DETONATION FROM THE SINGLE PRIMER. "A" TO THE OUT- 
SIDE LINES. THIS IS USED WHEN NO BLASTING MACHINE IS AVAILABLE 



APPROXIMATE TABLE OF CHARGES OF DU PONT STRAIGHT 50% 
DYNAMITE FOR BLASTING DITCHES WITHOUT A 
BLASTING MACHINE . 



Top Width 
of Ditch 


Approximate Number of Cartridges Per 

Hole Required for Ditches of 

Various Depths 


Number of 

Parallel Rows 

Required 


Distance 

Between Rows 

in Inches 




2H to 3 ft. 


4 ft. 


5 ft. 


6 ft. 




6 
8 

10 
12 
14 
16 
18 




2 

2 
2 
2 
2 
2 
2 


3 
3 
3 
3 
3 
3 
3 


5 
5 
S 
5 
5 
5 
5 


1 
1 or 2 
2 
2 
2 
3 
3 


30 
36 
42 
48 
36 
42 



Distance between holes in rows 16 to 24 inches to be determined by 
3 or 4 test shots. It is impossible to specify exactly, because soil con- 
ditions differ greatly, which makes a diiiference in spacings and loads. 

85 



PUTTING DOWN THE HOLES 

Ordinarily in swamp soils the bore holes can be put down with 
little effort. If the soil is at all hard, or has a heavy crust, the fastest 
tool is a good sharp crowbar, but if soft and mucky, a heavy tamping 
stick will suffice. The holes should not be left open, but should be 
loaded at once, as they cave in or become filled with floating slime. 

AMOUNT OF DYNAMITE REaUIRED FOB, A GIVEN LENGTH 

OF DITCH 

In order to enable the blaster to calculate the amount of dynamite 
required to cut various size ditches, the following table used in con- 
junction with the preceding table should prove very useful : 





10 Rods 


M Mile 


Vi Mile 


Spacing 

between 

holes in 

row 


Number 

of 

boles 


Dynamite required 

using charges 

per hole of 


Number 

of 

holes 


Dynamite required 

using charges 

per hole of 


Number 

of 

holes 


Dynamite required 

using charges 

per hole of 


cartridge 


Whole 
cartridge 


cartridge 


Whole 
cartridge 


cartridge 


Whole 
cartridge 


18 ins. 


110 


28 lbs. 


55 lbs. 


880 


220 lbs. 


440 lbs. 


1760 


440 lbs. 


880 lbs. 


20 " 


99 


25 " 


49 " 


792 


198 " 


396 " 


1584 


396 " 


792 " 


24 " 


83 


21 " 


41 " 


664 


166 " 


332 " 


1328 


332 " 


664 " 


26 " 


76 


19 " 


38 " 


608 


152 " 


304 " 


1216 


304 " 


608 " 


28 " 


71 


18 " 


36 " 


566 


142 " 


284 " 


1132 


283 " 


566 " 



1 rod — 16^ feet. 
10 rods — 165 feet or 55 yards. 
K mile— 1320 feet or 440 yards or 80 rods. 
}i mile— 2640 feet or 880 yards or 160 rods. 

For larger ditches requiring heavier loading or several parallel 
rows of holes increase the total amounts accordingly. These amounts 
also apply to ditching with a blasting machine. . 



DITCHING WITH A BLASTING MACHINE 

While it is possible to blast ditches by the propagated method, 
that is, without blasting machine, only in wet soils the electric method 
can be employed in any class of material, dry sand excepted, and low 
strengths of low freezing Red Cross can be substituted for the more 
sensitive Straight dynamite. 

The layout of the ditch is exactly the same as for the other 
method, but as an electric blasting cap is used in each hole it is pos- 
sible to space them farther apart in the row. The normal distances are 
from 24 to 32 inches for small ditches, and up to 48 and 52 inches for 
large ditches. 

86 



Different Explosives for Different Classes of Work. — The explosive 
selected for electric ditch blasting will depend upon the soil and size of 
ditch. In a medium loam, where only a small ditch (about two feet 
deep and three feet wide), is desired, the selection may be Red Cross 
Stumping Powder or Red Cross Extra 30 or 40 per cent. Where the 
material is very sandy Red Cross Gelatin 40 per cent, will give best 
results. It is practically impossible to blast ditches in dry sand. 

For larger ditches, or where there is much trouble with stumps and 
roots, a stronger explosive will give more economical excavation, and 
Red Cross Extra 40 per cent, or Red Cross Gelatin 40 per cent, should 
be selected. Where the work is very wet, and the charges must be left 
in the water for a long time, the Gelatin should be selected, as it is more 
water-resisting than the Extra. 

Red Cross Gelatin 40 per cent, also gives the best results in coarse 
sandy loam soils. 

A— A SMALL DITCH REQUIRES BUT ONE ^ 

LINE OF HOLES LOADED WITH LIGHT 
CHARGES— USUALLY ONE CARTRIDGE 
EACH 



B— LARGER DITCHES ARE BLASTED 
WITH A SINGLE LINE OF HOLES CON- 
TAINING INCREASED AMOUNTS OF 
EXPLOSIVES 



C— FOR STILL WIDER DITCHES TWO 
LINES OF HOLES ARE USED. THE 
CHARGES MAY BE OF SEVERAL 
CARTRIDGES 



D— DITCHES WIDER THAN 12 TO 14 
FEET ARE USUALLY LOADED WITH 3 
LINES OF CHARGES 



FIG. 58. VARIATIONS IN THE NUMBER OF LINES OF HOLES AND THE CHARGES 
ARE MADE TO SUIT THE SOIL CONDITIONS AND TO EXCAVATE DITCHES 
OF DIFFERENT SIZES 




METHODS OE lOADING 

After three or four trial shots similar to those described for wet 
ditching have established the proper depth and spacing of the holes, and 
the amount of dynamite per hole, the blaster is ready to begin actual 
operations. The holes may be put down with a subsoil punch, crowbar, 
soil auger, or any other tool suitable for the particular class of soil. 

87 



Unless water covers all charges they should be thoroughly tamped. 
It is best to punch only enough holes for one blast, load them and fire, 
before putting down more, as they are likely to be filled up or covered 
with trash thrown up by the blast. Do not overload the blasting 
machine. If its rated capacity is thirty charges, do not attempt to fire 
more than that at a time. 

When only one cartridge is used in a hole it must contain the 
electric cap, and should be pressed well down to the bottom of the hole 



DUPieX l£/ID/Aie IV/fl^ rO BLAST/KG MACM/A/E- 
COSNECTING WIRE TO l£AD//V6 W/fl£ 




FIG. 59. LONGITUDINAL SECTION, SHOWING METHOD OF LOADING WITH 
ELECTRIC BLASTING CAPS FOR BLASTING A DITCH. THE DIMENSIONS 
GIVEN ARE RECOMMENDED ONLY FOR MAKING THE FIRST TRIAL SHOTS 
FOR DETERMINING THE REQUIRED LOADING 




A — Method of connecting up one line of holes 



B — Another method of connecting up one line of holes 




C — Method of connecting two lines of holes 




D — Method of connecting three lines of holes 



FIG. 60. FOUR METHODS OF CONNECTING ELECTRIC BLASTING CAP WIRES 
FOR BLASTING DITCHES. THE BLACK DOTS REPRESENT LOADED HOLES. 
THE ELECTRIC BLASTING WIRES SHOULD ALWAYS BE LONG ENOUGH TO 
REACH FROM ONE HOLE TO THE NEXT, AS THIS OVERCOMES THE NEED OF 
USING CONNECTING WIRE 

88 



and tamped so that no air space is left to reduce the effect of the 
blast. When several cartridges are used in each hole, the primer should 
be on top, with the cap pointing downward. All holes, unless standing 
water covers the charge to a depth of several inches, must be well 
tamped. (See page 26 for Methods of Making Electric Primers, and 
pages 27 and 28 for Methods of Loading.) 

As the work progresses the soil should be carefully watched, and 
any needed variation made in the loading so that it may always conform 
to the material to be lifted. 

BLASTING LARGE DITCHES WITH A BLASTING MACHINE 

When larger ditches are desired the loading may be in deeper 
holes, using more or a higher strength of explosive; or one or two 
more parallel lines of holes may be employed, especially where wide but 
shallow ditches are needed. Where very deep ditches are needed, blast 
a wide, shallow ditch with two or three parallel rows of holes, and then 
load one or two rows in the bottom of the shallow ditch, and blast 
another ditch in the bottom of the first one. This latter method has 
been very efficient in opening large ditches eight or nine feet deep 
through heavy bottom lands for the correction of stream channels. 



LARGE DITCH SUCCESSFULLY BLASTED 

At the 1913 meeting of the North Carolina Drainage Congress an 
effort was made to straighten a creek. The ditch needed was 8 feet 
deep and 18 feet wide. The surface soil was light and full of roots. 
The subsoil was a heavy, wet clay. Three rows of holes were put 
down to a depth of from 30 to 36 inches, spaced 4 feet apart and 
loaded with Red Cross 40 per cent. The blast removed the soil to a 
depth of about 30 inches. In the bottom of this shallow ditch two rows 

FIG. 61. FOR EXCAVATING THE TOP 
CUT, THREE LINES OF HOLES WERE 
SPACED 4 FEET APART EACH WAY. 
THE DOTTED LINE INDICATES THE 
DEPTH OBTAINED BY THIS BLAST 

of holes were put down, spaced 4 feet apart, to the desired depth of 
ditch and loaded a little more than half full of 40 and 60 per cent. Du 
Pont. This blast threw out the soil to the desired depth and left the 
completed ditch fully up to the desired size, 8 x 18 feet. The cost was 
between 12 and 13 cents the cubic yard, which was a little high for the 
work, as the loading was too heavy. For a larger job lighter charges 
would have been used and a net saving in cost would have resulted. 
Extreme care, in observing the first trial shots, should always be 
exercised. 

89 





FIG. 62. FOR THE BOTTOM CUT TWO 
LINES OF HOLES, DOWN TO THE DE- 
SIRED GRADE, WERE SPACED FOUR 
FEET APART. THE HEAVILY SHADED 
PORTION REPRESENTS THE EARTH 
EXCAVATED BY THE SECOND BLAST 



TABLE or CHARGES FOR ELECTRIC DITCH BLASTING 





Approximate Number of Cartridges 






Approximate 
Top Width of 
Ditch in Feet 


of Red Cross Stumping Powder 

Required for Various 

Depths 


Number of 
Rows of Holes 


Distance 
Between Rows 




2H to 3 ft. 


4 


5 to 6 ft. 




3 


1 






1 


inches 


6 


2 


4 


6 


1 


" 


8 


2 


4 


6 


1 or 2 


20 " 


10 


2 


4 


6 


2 


28 " 


12 


2 


4 


6 


2 


36 " 


14 


2 


4 


6 


2 


42 " 


16 


2 


4 


6 


3 


42 " 



Required length of 
No. 6 Du Pont 
Electric Blasting 
Cap Wires 



4 ft. 



6 ft. 



6 to 8 ft. 



Although this table is necessarily but an approximation, it will 
serve as a good basis for estimating ditch charges. 

Practice makes perfect in ditch blasting the same as in anything 
else. The way to get the practice is by blasting short test sections of 
about ten holes each until the proper loading for the soil condition is 
determined. After blasting a few ditches, less experimenting in the 
beginning will be necessary. 

STREAM CORRECTION 

Each spring the big freshets in creeks and rivers are the cause 
of much property loss. Bottom lands are either washed away or cov- 
ered with a layer of sand that is too thick to plow under, and the 
fertility of the soil is greatly reduced. 

Permanent control of streams subject to overflow is expensive 
if undertaken in haste. Equally good results may be obtained with 
much less expense by undertaking the work in a slower but more 
systematic way, which will permit the stream to do most of the actual 
digging itself. 



90 



A great part of the filling up of stream courses is caused by logs 
and other floating material forming rafts and sand bars in the chan- 
nels. Another fruitful source of trouble is from out-crops of rock 
which divert or impede the normal flow of the current. Overhanging 
stumps and trees along the banks lend still further obstruction. Sharp 
bends in the course of the stream check the current and cause trouble 
by forming sand bars. 

Any and all of these troubles may be overcome quickly and at rea- 
sonable cost by the use of dynamite. Shoot out the raft and logs, and 
blast a sufficient channel through the confining rock. (See pages 52 to 
56 for Methods of Blasting Boulders and Ledges.) A well-placed blast 
will cause the overhanging stumps or trees to immediately vacate. 
(See Fig. 63.) 



FIG. 63. AtETHOD OF LOADING A 
STUMP OR TREE TO BLAST IT FROII 
THE BANK OF A STREAJL IT IS BEST 
TO FIRST CUT THE TREE OFF NEAR 
THE GROUND LINE AND LOAD THE 
STUJIP HEA\'Y ENOUGH TO BLOW IT 
ACROSS TEIE STREAM. FOR LARGE 
STUMPS DISTRIBUTED CHARGES AND 
ELECTRIC FIRING ARE RECOM- 
MENDED. THE USE OF TEAMS FOR 
DRAGGING LOGS AND STUMP FRAG- 
MENTS OUT OF THE CHANNEL IS 
HIGHLY RECOilMENDED 



5^^-;-J=«?5=----_ 




The cutting oil of sharp turns in the channel will take a little more 
time and should be well done in the beginning. Locate the line of the 
new cut-off and blast a ditch that will at all times carry a part of the 




FIG. 64. DIAGRAM OF STREAM TROUBLES THAT MAY BE 
CORRECTED BY BLASTING 

91 



flow. When this is done and the rafts and logs are out of the way- 
above and below, all there is left to do is to wait for the heavy rains 
to flood the streams. The increased rate of flow will cause the water 
to cut and wear away at the bottom of the channel as well as at the 
sides. From time to time it will be best to go over the stream and 
make sure that no new obstruction is being formed. 

Small blasted ditches have been scoured out by the current until 
they are now carrying the entire flow of large streams. With a little 
help now and then any stream with a fair fall can be made to do won- 
ders in making itself a permanent and suitable course. 



FIG. 65. METHOD OF LOADING FOR 
WIDENING A STREAM CHANNEL. 
ELECTRIC FIRING IS BEST, UNLESS 
THE . GROUND IS WET ENOUGH TO 
PERMIT FIRING BY THE PROPAGATED 
METHOD. THE LOADING SHOULD BE 
HEAVY ENOUGH TO BLOW ALL THE 
WASTE MATERIAL ENTIRELY OUT OF 
THE CHANNEL 




For deepening stream channels, the bottoms of which are too hard 
to permit erosion, the loading is done exactly as in ditch blasting. 




FIG. 66. METHOD OF LOADING, WHICH 
MUST BE HEAVY ON ACCOUNT OF 
THE BURDEN OF WATER, FOR DEEP- 
ENING A STREAM. EITHER ELECTRIC 
OR PROPAGATED FIRING CAN BE 
PRACTICED 



Either method of firing can be followed. The loading must be heavy 
on account of the added weight of water that must be lifted. 



VERTICAL DRAINAGE OF WET SPOTS 

It is sometimes very difficult to devise a method of draining a 
land-locked depression. Generally speaking, ditching is the proper 
solution of the problem, but that calls for an outlet and at least some 
degree of slope, which are hard to locate under the conditions described. 

Ponds and wet spots are caused by impervious soil beneath them. 
By blasting this impervious stratum, perfect drainage can sometimes 
be brought about. Certain conditions must exist, however. First, 

92 



it must be ascertained by means of a soil auger that there is a stratum 
of gravel or sand beneath the impervious layer that will carry off the 
surface water if it is drained down into it. 



FIG. 67. WHEN PONDS ARE CAUSED BY 
TIGHT MATERIAL OVER OPEN MATE- 
RIAL THEY CAN BE DRAINED BY 
DEEP BLASTING. NOTE THE LOCA- 
TION OF THE EXPLOSIVE CHARGE 




The character of the soil forming the impervious layer must 
also be noted. If it is shale or a true hardpan that will remain broken 
up when blasted, the blasting alone, provided it breaks all the way 
through to the water-carrying stratum of sand or gravel, wilf prove 
sufficient to drain the surface. 

On the other hand, if the impervious layer consists of a fine sticky 
clay, it will run together again, if blasted, and the drainage will stop 
because of the clogging of the outlet. Under these conditions a bore 
hole should be put down to within about a foot of the sand or gravel. 
If this stratum lies over thirty feet below the surface, this method of 
drainage is impractical. At the bottom of the bore hole a chambering 
shot should first be made by using a cartridge or two of dyna- 
mite. In the chamber thus formed a load of from five to twenty-five 
pounds of 40 per cent, dynamite (the amount depending upon the depth 
of the hole) should be placed. Cartridges should also be strung all the 
way up the bore hole to within about two feet of the top. As the car- 
tridges will all be in contact, one primed cartridge' at the top of the line 
will fire the entire charge. The object is to blast out a well or sink 
hole. Such a shot should form a rough well from the surface down to 
the sand. If the soil is of a wet, heavy, clay type, it should not cave 
much. This well or sink hole should then be filled with cinders, loose 
stone, stump fragments, or some other material that will prevent the 
clay from running together again. Such a sink hole should drain the 
pond or wet spot. 

The hole should be put down at the lowest point in the surface ; 
that is, the point to which surface water would naturally run. If the 
wet spot is a large one covering considerable area, it will probably be 
necessary to construct several sink holes in the bottom in order to get 
desired drainage. 

In order to determine the depth required, a test hole is bored with 
a dirt auger, which should be pulled up from time to time in order to 
clean the hole out, and also to ascertain the nature of the soil encoun- 

93 



tered, which is readily seen on the spiral thread of the auger. Once 
the water-absorbing sand or gravel is reached the depth of the hole 
is noted on the auger shank. This test hole may be tamped full of 
soil to about 6 inches above the sand or gravel in shallow holes, and 12 
to 18 inches in deep holes. This is done because it is not advisable to 
load the charges in the sand or gravel. They should be located in 
the hardpan stratum. 



>iJt.rf> jijut 




FIG. 68. DIAGEAM OF DEEP DRAINAGE 
HOLE, SHOWING THE USE OF TRASH 
TO PREVENT THE HOLE BECOMING 
CLOGGED WITH FINE CLAY. THE 
BLASTED CRATERS MUST EXTEND 
THROUGH THE CONFINING HARDPAN 
OR CLAY AND INTO OPEN WATER 
BEARING MATERIAL BELOW 



It very often happens that holes have to be bored to depths aver- 
aging from 15 to 30 feet before the water-absorbing strata are reached 
and in order to do this it is necessary to use an extension auger or 
long churn drill. If the water is too deep to work in, the boring should 
be done from a raft. It is much easier to operate the auger through 
a hole in the center -oi the raft than over the side. As soon as the 
hole has been bored to the required depth the auger is withdrawn and 
a piece of 1^-inch pipe sufficiently long to reach the bottom of the hole 
and 5 or 6 inches above the water level is inserted. Through this the 
dynamite cartridges are dropped one at a time and pushed to the bottom 
with a wooden tamping rod. A good firm push will hold each cartridge 
in position. The last cartridge but one is primed with a Du Pont 
Waterproof Electric Blasting Cap and one cartridge is put on top of 
it to hold it in place, as it is not advisable to give the primed car- 
tridge too hard a push with the tamping rod. 

When the hole has been charged the loading pipe is withdrawn 
and slipped over the ends of the electric blasting cap wires, the leading 
wires are connected on to the electric blasting cap wires, the joints being 
carefully protected with insulating tape and the raft is poled to the shore 
or a safe distance away from the hole while the leading wire is carefully 
paid out. The outer ends of the leading wires are then attached to 



94 



the blasting machine, the operation of which explodes the charge. It 
is unnecessary to do any tamping in this work if the holes are filjed with 
water. The cartridges should not be slit. The explosive to use is Red 
Cross Extra Dynamite 40 per cent., or Red Cross Gelatin 40 per cent. 
The following table gives the approximate charge for holes of different 
depths : 



Depth of Hole 


Approximate Number of 
l)i"x8" Cartridges 


5 feet 


5 


10 " 


12 


15 " 


20 


20 " 


25 


30 " 


40 


40 " 


50 







Where the ground is swampy or ponds form in the wet season only 
and dry up later in the year, the blasting should be done in the dry 
season when a raft will not be required. This blasting should be done 
just as described above except that it is necessary to tamp the charge 
thoroughly unless the bore hole fills up with water. In this work it is 
sometimes of advantage to make a chamber in the bottom of the hole by 
first exploding a single cartridge in the bottom. This makes it pos- 
sible to get more of the main charge into the bottom and break the 
rock or subsoil better. The explosion of the single cartridge may close 
the hole a little, but it can easily be opened again with the auger or an 
iron rod. The main charge must never be loaded immediately after 
chambering, but a half hour or more allowed for the bottom of the 
bore hole to cool off. This plan of chambering the bottom may also be 
followed when water fills the bore holes. 

It should always be remembered that the first and most essential 
feature of drainage is the control of the rainfall; that is, holding it 
in the subsoil by proper tillage where it can nourish the crops. If 
proper attention is paid to this feature better crops will be produced 
and the need of heavy ditching materially reduced. 

SINKING WELLS 

Wells are often sunk through rock or ground which cannot be dug 
to advantage without the aid of explosives. When rock is reached 
and the earth above is properly supported, a circle of four or five drill 
holes should be started about half-way between the center and the sides 
of the well and pointed at such an angle that they will come closer 
together near the center when they are three or four feet deep (Fig. 
69). These holes should be loaded about half full of Red Cross Extra 

95 



Dynamite 40 per cent., with damp clay or sand tamping packed firmly 
above to the top of the hole and then exploded all together from the 
surface by electricity. This shot will blow out a funnel-shaped opening 




FIG. 69. THE FIRST OR CUT HOLES ARE 
DRILLED NEAR THE CENTER OF THE 
WELL, AND SHOULD NEARLY MEET 
AT THE BOTTOM 



FIG. 70. WHEN THE FIRST HOLES ' 

HAVE BROKEN OUT A CONE-SHAPED ; 

CUT THE WELL IS WIDENED TO ITS - 

FULL DIAMETER BY ANOTHER ; 

ROUND OF SHOTS DRILLED PRACTI- /A 



CALLY STRAIGHT DOWN 



V/ 




in the center, and the well can then be made full size with another 
circle of holes drilled straight down as close to the sides as possible 
(Fig. 70). If the well is large it may be necessary to drill a circle of 
holes between the inner and outer circle. The above process should be 
repeated until the well has passed through the rock or has been sunk 
to the necessary depth. Do not in any case enter a well until all the 
fumes of the last blast have come out. If in doubt, lower a lighted 
candle to the bottom; if it continues to burn the well may be entered 
safely. Electric blasting caps will give the best results. 

SHOOTING WELLS TO INCREASE THE FLOW OF WATER 

Often drilled or dug wells do not give a sufficient flow, the water 
being confined in a number of small veins or fissures that do not dis- 
charge into the well. The object of shooting a well is to open up these 
veins or fissures so that all of the confined water is brought together. 
Where such formations are found correct blasting will usually result in 
increasing the flow. 

Where wells are drilled in dry, non-water-bearing rock, shale, clay 
or gravel shooting will not produce a flow. 

The services of an experienced well shooter should always be 
secured, and well shooting should never be attempted by the novice in 
the use of explosives. The Du Pont Company will be glad to corre- 
spond with those having work of this kind to do and who cannot get 
the services of a competent shooter. In writing for information be 
sure to answer all of the following questions : 



96 



FOR DRILLED WELLS 

1. Location of well. 
. 2. How many feet is well from nearest buildings ? 

3. Kind of buildings. 

4. Diameter of well in inches. 

5. Diameter of casing in inches. 

6. Depth of well in feet. 

7. Depth of casing in well in feet. 

8. How many feet of water in well? 

9. Describe the different kinds of soil, rock and other material you 
went through in drilling the well, and give the location and depth of 
each class of material. 

10. Can the water be partially or entirely exhausted from the well ? 

11. What is the maximum number of gallons of water the well will 
furnish in an hour? 

FOR DUG WELLS 

1. Depth of well. 

2. Diameter of well. 

3. Type of curbing. 

4. Character of rock below the bottom of the well. 

5. Has the well always given a poor flow or has the trouble devel- 
oped recently? 

6. Are there any neighboring wells on land as high as yours that 
are giving a good flow ? If so, how deep are they ? 

EXCAVATING CELLARS AND FOUNDATIONS 

When it is necessary to make such excavations in rock, the first 
or "cut" shot should be made with a circle of holes running down to a 
point as has been described for well sinking (page 96). After one 
small section is down to the required grade the rest of the holes should 
be drilled straight down. These should be spaced back a distance equal 



FIG. 71. METHOD OF LOADING FOR EX- 
CAVATING CELLARS AND OTHER PITS 




to the depth of the cut and spaced about the same distance apart. When 
the cut is more than six feet deep, the spacing should not be as great 
as the depth, as more than six feet is hard to blast off. 

In reasonably hard rock the drill holes should be loaded a little 

97 



more than half full of Red Cross Extra 40 per cent., removed from 
the shells and tamped tight. Better results will be obtained with elec- 
tric blasting, because then several charges can be fired together, giving 
a cumulative effect. 

In tight clay an opening can be started with a single hole not quite 
down to grade and loaded with enough dynamite to blow out a conical 
shaped section of earth. After this is cleaned out, the rest of the holes 
can be loaded with lighter charges. 

See pages 27 to 29 for correct methods of loading and firing. 



KOAD BUILDING 

A rational use of explosives in road building for clearing the right 
of way, blasting protruding stone from the surface or from the sides 
of cuts, making cuts through stone or tight clay, digging ditches, reduc- 
ing grades, widening cuts, and various other purposes, will hasten the 
completion of the work and reduce the cost. 



FIG. 72. LOCATIONS OF BORE HOLES 
FOR ROAD GRADING IN HARD 
GROUND. ELECTRIC FIRING IS 
RECOMMENDED 





FIG. 73. PLAN OF APPROXIMATE LOADING FOR CUT WORK 




FIG. 74. METHOD OF LOADING 
TO WIDEN A ROAD CUT. ELECTRIC 
FIRING IS ADVISED 



The methods already described for stumping, boulder blasting and 
ditching, are equally applicable to this class of work. The loosening 
of tight clays in reducing grades is done in exactly the same way as in 
digging cellars described under the preceding heading. 

98 



In starting in a rock cut the ordinary practice is to drill the holes 
a few inches below the desired grade. These holes should be spaced 
back and apart a distance about equal to the depth of the cut, unless 
the holes are more than six feet deep, when the spacing should be 
about six feet. Each row of holes should be fired simultaneously with 
electric caps and a blasting machine. 




28. 



FIG. 75. ELEVATION OF APPROXIMATE LOADING FOR CUT WORK 

Full directions for priming and loading are given on pages 26 to 



"Road Building and Maintenance" gives detailed information on 
Road Building. A copy may be had on application. 

ICE BLASTING 

Often in Spring when ice in streams starts to move, it gets choked 
in narrow parts of the stream or by some natural or artificial obstruc- 
tion. Then an ice gorge or jam is formed which causes the water to 
back up, flooding the surrounding territory above and often carrying 
away bridges and other structures and causing considerable damage. 

By the use of explosives at the proper time the damage can often 
be averted. Ice begins to move out in various localities about the 
same time each year. Usually there is sufficient warning when to 
expect the break to occur, by several days' thaw or rains. It is a good 
plan to anticipate the moving out as soon as the Spring thaw begins, 
by blasting the ice while intact on that section of the stream where the 
gorge or choke usually occurs. The method of procedure is as follows : 
With ice spuds or cutters and bars, chop holes about six inches to eight 
inches in diameter through the ice to the water. Holes should be spaced 
from fifteen to twenty feet apart. 

A charge of from six to eight cartridges (if the ice is, thick this 
must be increased) of low freezing explosives 40 per cent, strength 

99 



should be lowered in each hole so that the explosive is in the water and 
below the ice. The cartridges can be tied together in a bundle, and one 
cartridge of each bundle should be primed with a No. 6 Electric Blasting 
Cap. To prevent the loss of the charge the wires can be fastened to a 
stick of wood laid across the hole on surface of the ice. Several holes 
should be connected together in series and fired with a blasting machine 
and electric blasting caps. 

It has been found that the ice is broken up more by the wave action 
of the water than when the charge is imbedded in cracks or holes dug 
in the ice. It is best to fire the holes electrically, but if no blasting 
machine is at hand a cap and fuse will answer, but then only one hole 
at a time can be fired. 

If this is done all through the narrow section of the stream the ice 
is practically "honeycombed," so that when the water and ice from 
above comes down, it gives way readily and causes no damage. 

If the gorge or jam has actually formed a charge of from five 
to twenty-five pounds ( in some cases much more i of dvnannte should 
be loaded in a crevice, or dug hole, at the key or pivotal point of the 
gorge. Several such charges can be distributed at various points in the 
gorge and connected and fired electrically. If the first blast does not 
start the gorge, the same process should be repeated with increased 
charges until it gives way. 

To break up floating ice so that it will not bank up, forming a 
gorge, charges of dynamite can be exploded on the surface of the ice, 
the size of the charge depending on the thickness of the cakes. 

If they are large blocks it may be possible to get on the ice from 




FIG. 76. DIAGRAM SHOWING LOCATION OF ROW OF HOLES FOR 
BLASTING AN ICE GORGE 

100 



shore or boats and successive charges of several cartridges can be 
exploded with fuse and blasting cap until the ice cake is properly 
broken. 

If the stream is narrow the charge of explosives can be thrown on 
the ice from the shore, or, if the current is too swift the charge can be 
dropped on the floating cakes from down-stream side of bridges. The 
dynamite should be tied in a bundle and one cartridge in each bundle 
primed with a blasting cap and fuse. A block of wood or stone can be 
tied to the charge as an anchor to prevent its rolling off the cake of ice. 
The fuse should be lighted before being thrown and ample length 
allowed for a geta\\-ay. Fuse burns about two feet per minute, so 
from two to three feet is usually sufficient. The place where fuse 
enters blasting cap should be smeared with soap or grease to protect 
charge in cap from water. 

Watering places for stock along the banks of streams can be 
easily kept free from ice in winter b_\' the use of a little dynamite from 
time to time. 

STARTING LOG JAMS 

To start log jams with dynamite the charge of several cartridges, 
or in some instances of many pounds of dynamite, is exploded on or 
under the logs forming the key of the jam. When small charges 
are enough, the cartridges are tied in a bundle as when blasting ice. 
If charges of hfty pounds or more are necessary the dynamite may be 



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BLASTING OUT A LOG JAM WITH DU PONT DYNAMITE AT 
BIG FORK, MONT. 

101 



put in a bag or left in the original wooden cases. The charge is 
primed with an Electric Blasting Cap and after being finnly secured in 
the proper position is exploded from the shore with a blasting machine. 

Blocks in log rollways caused by rain and snow freezing and 
binding the logs together are broken up by exploding charges of dyna- 
mite in different places under the logs until they are loosened and can 
be rolled apart. 

Red Cross Extra Dynamite 40 per cent, is recommended for start- 
ing log jams and for opening the rollways. See pages 22 to 29 for 
proper methods of priming, charging, tamping and firing. 

SCRAPPING OLD MACHINERY 

Breaking up old machinery, such as heavy castings or steam 
boilers, can be readily done with dynamite. 

For scrapping a boiler use only 40 per cent, or stronger explosives. 
Remove the dynamite from the shell and distribute in a continuous 
cord about half an inch in diameter all the way around the boiler, and 
secure it with a heavy mudcap. This can be placed along one of the 
seams more easily than on the smooth plates. When detonated such 
a charge will cut the plates almost as neatly as a shearing machine, 
and will reduce the cumbersome boiler to a size that can be handled. 

For breaking heavy castings mudcapping is practiced the same as 
on boulders (Fig. 35). Sometimes a hole in the casting can be used 
for a block hole and loaded as described on page 52. 




A IIE.W'V .METAL RETORT TII.\T W.\S BROKEN UP BY .\ BL.VST 

102 



Large vessels and even boilers can be broken up by first filling them 
with water, and, if possible, closing all openings. The dynamite is 
primed and suspended in the water near the bottom or the thickest 
metal, but must not be in actual contact with the metal. The explosion 
of such a charge transmits a powerful blow to all sides and shatters 
them. (See Fig. 77 for diagram of loading.) 




FIG. 77. SHOWING BURSTING CHARGES 
IN A LARGE VESSEL FILLED WITH 
WATER. THEY ARE SUSPENDED ON 
CORDS SO THAT THEY DO NOT 
TOUCH THE METAL. ELECTRIC FIR- 
ING IS BEST 



DIGGING ICE AND FISH PONDS 

The growing interest in fish culture, one of the moves to provide 
a toothsome substitute for expensive meats, calls for the digging of 
fish ponds. These are generally located in low, wet lands where blasting 
has a great advantage over other methods of digging. The methods 



FIG. 78. DRAG SCRAPER SUITABLE FOR 
MOVING BLASTED GROUND IN FIN- 
ISHING FISH PONDS, GRADING ROADS, 
FILLING GULLIES, AND DOING MANY 
OTHER CLASSES OF WORK 



of blasting are exactly the same as for ditching (see pages 78 to 90). 
It is usually best to dig the ponds quite long and not more than 25 
feet wide, as there is much difficulty in shooting the soil out of wider 
ponds. When greater width is desired, a part of the soil can be blasted 
out and the rest removed by small drag scrapers (Fig. 78). 

The methods of digging ice ponds are the same. 

Digging Ponds or Holes in Running Streams. — Many shallow 
streams afford excellent locations for fish, duck and bathing holes. 
Improvement is by creating pools. This is done by blasting out the 
bottom of the channel as is shown in Fig. 66, page 92. This loading 




103 



should extend along the stream only as far as it is desirable to make 
the pond. A log thrown across the stream just above the pool, in such 
a way as to cause a slight waterfall, will produce a scouring action and 
keep the pool well cleaned. 

DIGGING POST AND POLE HOLES 

To speed up the \\ork and decrease the cost, many post and pole 
holes are now blasted. The method employed will depend on the 
depth of the holes and the nature of the ground. 

When hard ground is encountered and the location of the hole 
determined, first remove the soft surface to a depth of from 6 to 8 
inches, or down to the hard ground, and to the full diameter of the 
desired hole. This will prove helpful even where there is but a few 
inches of soft ground and for deep and shallow holes. The hole is then 
ready for punching the bore hole for loading. 

The bore hole should be located in the center of the shallow hole 
already shoveled out. It should be 1^ inches in diameter. Where 
deep holes are needed it should be 2 inches in diameter, as there must 
be room for loading the long charge of dynamite. 

The method of punching the bore hole depends on the nature of 
the ground. In clay it may be easily put down by means of a long 
churn drill, using a little water. For harder ground a heavy drive 
point or drill can be driven down and loosened by pounding on the 
sides, so that it can be easily removed. 

The use of a soil auger is often required for finishing the bottoms 
of very deep holes where churn drilling or punching is difficult. 

Holes can be made entirely by the use of the auger, but this is 
usually more expensive than punching. When the soil is too dry to 
stick to the auger, a little water should be poured into the hole. This 
forms mud that can be easily lifted out. 

Hard shale and rock require the use of rock drills. 




RESi'M,^ 111' \ i;i. ,\sr im; \ iii':i:i' ikji,!-:, i:iik strkaie was Mvr r.LijwN 

OUT, IfUT WAS SLIGHTLY- RAISED. BELOW A DEEP AND WELL-SHAPED 
HOLE WAS FOUND. THE COST REDUCTION, AS COMPARED TO HAND DIG- 
GINf,. WAS AnOUT 50 PER CENT. 

104 



Frequently pebbles or clods fall into the bore holes before they 
are loaded. These, naturally, prevent the charge being correctly 
placed, and so must be removed. The best tool for doing this is a 
spoon, such as is shown in Fig. 5. This is useful for both deep and 
shallow holes. 

Blasting Shallow Holes. — Shallow holes are ordinarily blasted by 
using a half, or, if the ground is very hard, a whole cartridge of Red 
Cross Farm Powder, Red Cross 
Stumping Powder or Red Cross 
Extra Dynamite 20 to 40 per cent. 
This is primed and loaded in the 
bottom of the bore hole, usually 
without tamping. (See pages 22 to 
26 for Methods of Making Prim- 
ers.) Either blasting caps and fuse, 
or electric blasting caps may be 
used. 

The effect of such a blast is to 
force back the soil and form a "pot 
hole" at the bottom, and loosen the 
soil above so that it may be easily 
spooned or shoveled out. This 
avoids the necessity for using a 
chisel or other tools to loosen the 
hard ground. 

The greater part of the ground 
is packed back into the wall and 
bottom, especially if it is wet or 
moist when the blasting is done. 
Some loose soil is usually left at 
the bottom of the hole. 

Blasting Deep Holes. — The method of loading must be changed for 
deep holes, or else a tight bridge or plug of dirt will be left at the top. 
To prevent this, the charge must be distributed along the hole as is 
shown in Fig. 80. This is done in order to get more uniform lateral 
expansion of the gases along the bore hole. 




FIG. 79. 



LOADING FOR A SHAL- 
LOW HOLE 



The primer is placed in the bottom and no 
tamping is used. The dotted line shows 
the approximate size and shape of the 
blasted hole 



JB= 



=fc 



=dt 



JB 



FIG. 80. DYNAMITE CHARGES TIED TO STICK AND READY TO LOAD 
FOR A POLE HOLE BLAST 



The amount of dynamite in each charge must be governed by the strength of the 
dynamite and by the hardness of the ground 

105 



To get this distribution use a straight, narrow lath, reed, or 
as long as the hole is to be deep. Cut the cartridges into two or 
pieces. Tie one piece of dynamite 
to the side of the stick at one end, 
from 6 to 20 inches further up tie a 
second piece. Continue this to 
within 12 to 24 inches of the top, 
depending on the nature of the soil 
and the results of trial shots (Fig. 
81). 

The charge thus arranged is 
placed, with the primer end up, in 
the hole, and fired. The need of 
tamping above the primer will de- 
pend on the nature of the soil. 



stick, 
three 





CITARnE 
FOR liLA 



Wrril PRIMF.R ON T,.\Tn 
STING A DEEP POLE HOLE 



Fir,. SI. METHOD OF LOADING FOR 
]:L.\STIXG .\ DEEP POLE HOLE, 
,S H O W I N G THE DISTRIBUTED 
CHARGE IN PLACE. THE DOTTED 
LINE INDIC.VrES THE APPROXI- 
MATE SIZE OF THE FINISHED 
MOLE 



It should be remembered that 
this method is useful only on clayey 
or other soils that can be packed by 
the explosion. Shales must usually 
be blasted as is advised for rock. 



106 



Blasting Holes in Solid Rock. — ')y 
As it is impossible to force back 
the sides of the holes in solid rock, 
as is done in blasting in hard clays, 
modifications in the method of load- 
ing are required. Ordinarily holes 
are not put down so deep in rock 
as in hard ground. 

After excavating the hole down 
through the soil, if any is present, 
drill a hole from 12 to 18 inches 
(Fig. 82) into the rock. Load this 
with a full cartridge primer pressed 
well to the bottom, tamp the hole 
tight, and fire. 

If the loading is heavy enough 
this will shatter the rock to the full 
depth of the blast. When the loose 
fragments have been removed, drill 
another hole to about the same 
depth and load as before. 

The explosive used for this 
work should never be of a lower 
strength than Red Cross Extra 40 
per cent, strength, and for hard 
rock 50 or 60 per cent, strength is 
often better. 

Those desiring additional in- 
formation on this subject, should 
write for "Blasting Pole and Post 
Holes." 



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1 1 




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FIG. 82. IN HARD ROCK THE BORE 
HOLE MUST NOT BE DEEP. AFTER 
THE FIRST BLAST CLEAN OUT THE 
FRAGMENTS AND DRILL A SECOND 
HOLE. DOTTED LINE INDICATES 
THE SHAPE OF THE BLASTED 
HOLE 



107 



PEECAUTIONS TO BE OBSERVED IN GENERAL WITH 
REGARD TO EXPLOSIVES 

DON'T forget the nature of explosives, but remember that with proper 
care they can be handled with comparative safety. 

DON'T smoke while you are handling explosives, and DON'T handle 
explosives near an open light. 

DON'T shoot into explosives with a rifle or pistol, either in or out of a 
magazine. 

DON'T leave explosives in a field or any place where animals can get 
at them. Cattle like the taste of soda and saltpeter in explo- 
sives, but the other ingredients would probably make them sick 
oi: kill them. 

DON'T handle or store explosives in or near a residence. 

DON'T leave explosives in a wet or damp place. They should be kept 
in a suitable, dry place, under lock and key, and where chil- 
dren or irresponsible persons cannot get at them. 

DON'T explode a charge to chamber a bore hole and then immediately 
reload it, as the bore hole will be hot, and the second charge 
may explode prematurely. 

DON'T do tamping with iron or steel bars or tools. Use only a 
wooden tamping stick with no metal parts. 

DON'T force a primer into a bore hole. 

DON'T explode a charge before everyone is well beyond the danger 
zone and protected from flying debris. Protect your supply 
of explosives also from danger from this source. 

DON'T hurry in seeking an explanation for the failure of a charge to 
explode. 

DON'T drill, bore or pick out a charge which has failed to explode. 
Drill and charge another bore hole at least two feet from the 
missed one. 

DON'T use two kinds of explosives in the same bore hole, except 
where one is used as a primer to detonate the other, as where 
dynamite is used to detonate Du Pont Low Powder. The 
quicker explosive may open cracks in the rock and allow the 
slower to blow out through these, cracks, doing little or no 
work. 

DON'T use blasting powder, permissible explosives or high explosives 
in the same bore hole in coal mines. 

108 



DON'T use frozen or chilled explosives. Dynamite other than Red 

Cross, often freezes at a temperature between 45° and 50° F. 
DON'T use any arrangement for thawing dynamite other than one of 

those recommended by the DU PONT COMPANY. 
DON'T thaw dynamite on heated stoves, rocks, bricks or metal, or in 

an oven, and don't thaw dynamite in front of, near or over a 

steam boiler or fire of any kind. 
DON'T take dynamite into or near a blacksmith shop or near a forge 

on open work. 
DON'T put dynamite on shelves or anything else directly over steam 

or hot-water pipes or other heated metal surface. 
DON'T cut or break a dynamite cartridge while it is frozen, and don't 

rub a cartridge of dynamite in the hands to complete thawing. 
DON'T heat a thawing house with pipes containing steam under 

pressure. 
DON'T place a hot- water thawer over a fire, and never put dynamite 

into hot water or allow it to come in contact with steam. 
DON'T allow thawed dynamite to remain exposed to low temperature, 

but use as soon as possible. 
DON'T allow priming (the placing of a blasting cap or electric blast- 
ing cap in dynamite) to be done in a thawing house. 
DON'T prime a. dynamite cartridge or charge or connect bore holes for 

electric firing during the immediate approach or progress of 

a thunder storm. 
DON'T carry blasting caps or electric blasting caps in your pocket. 
DON'T tap or otherwise investigate a blasting cap or electric blasting 

cap. 
DON'T attempt to take blasting caps from the box by inserting a wire, 

nail or other sharp instrument. 
DON'T try to withdraw the wires from an electric blasting cap. 
DON'T fasten a blasting cap to the safety fuse with the teeth or by 

flattening it with a knife ; use a cap crimper. 
DON'T keep electric blasting caps, blasting machines or blasting caps 

in a damp place. 
DON'T attempt to use electric blasting caps with the regular insulation 

in very wet work. For this purpose secure "Du Pont Water- 
proof" or "Gutta-percha Covered" Electric Blasting Caps. 
DON'T worry along with old, broken leading wire or connecting wire. 

A new supply won't cost much and will pay for itself many 

times over. 

109 



DON'T handle safety fuse carelessly in cold weather, for when cold it 

is stiff and breaks easily. 
DON'T store or transport blasting caps or electric blasting caps with 

high explosives. 
DON'T store safety fuse in a hot place, as this may dry it out so that 

uncoiling will break it. 
DON'T lace safety fuse through dynamite cartridges. This practice is 

frequently responsible for the burning of the charge. 
DON'T operate blasting machines half-heartedly. They are built to 

be operated with full force. They must be kept clean and dry. 
DON'T cut the safety fuse short to save time. It is a dangerous 

economy. 
DON'T expect a cheap article to give as good results as a high-grade 

one. 
DON'T expect explosives to do good work if you try to explode them 

with a detonator weaker than a No. 6 (red label). 
DON'T leave detonators exposed to the direct rays of the sun. 
DON'T leave detonators where the rays of the sun will strike them 

after passing through glass. 
DON'T have matches about you while handling explosives. 
DON'T store explosives so that the cartridges stand on end. 
DON'T open cases of explosives in a magazine. 
DON'T open cases of explosives with a nail puller, pick or chisel. 
DON'T prime both ends of a cartridge of explosive when making 

primers of half cartridges, with a blasting cap or electric 

blasting cap, before cutting it in two. Cut the cartridge in half 

and prime each piece separately. 
DON'T use a needle of iron or steel when firing by means of miner 

squibs. Use one of copper or brass. 
DON'T keep blasting caps or electric blasting caps in the same box or 

container with other explosives in the field. Keep them 

separate. , 



Explosives cannot be shipped by parcel post or express, nor can they 
be transported on a train carrying passengers for hire. They must be 
shipped as freight. 



110 



PRINCIPAL PRODUCTS MADE BY 
E. I. du Pont de Nemours & Co. 

Wilmington, Delaware, U. S. A. 

HIGH EXPLOSIVES: Red Cross Extra; Red Cross Gelatin; Red Cross 
Farm and Stump Powders; Red Cross Straight; t)u Pont Extra; Du font 
Gelatin; Du Pont Blasting Gelatin; Du Pont Stumping Powder; Du Pont, 
Red Star, Red Arrow (Export); Du Pont Straight; Repauno Gelatin; 
Repauno Stumping. 

LOW EXPLOSIVES: Du Pont R. R. P.; Du Pont F, FF, FFF. 

BLASTING POWDERS: "A" Brand having six standard granulations; 
"B" Brand having eight standard granulations. 

PERMISSIBLE EXPLpSIVES. Brands: Monobel and Carbonite— each 
brand made in six varieties to meet all blasting conditions in coal mines. 



SPORTING POWDERS: Smokele.s Shotgun — Brands r Dupont, 
Schultze, Empire (all Bulk) and Ballistite (Dense); Dupont Dense 
(Export); Black— Du Pont Rifle; Hazard Kentucky Rifle; Golden Phe'asant 
and Indian Rifle (Export). Black Powder for Fireworks. 

Rifle and Pistol Powders — Bulk — Brands: Du Pont No. 1 Smokeless 
Rifle; Gallery Rifle Powder No. 75; Sporting Rifle Powder No. 80; Schuetzen. 

Military Rifle Powders — Dense — Brands: Military Rifle Powders Nos. 
10, 20, 21; Improved Military Rifle Powder Nos. 15, 16, 18. 

Smokeless Pistol Powder — Brand; Du Pont Pistol Powder No. 3. Partly 
Smokeless Powdei^^Lesmok. 

MILITARY EXPLOSIVES: Cannon Powders— Black and Smokeless; 
Nitrocellulose; Trinitrotoluol; Picric Acid; Detonators; Primers. 



BLASTING SUPPLIES: Electric Blasting Caps; Delay Electric Igniters 
and Blasting Caps; Blasting Caps; Fuse; Electric Squibs; Blasting Machines; 
Miners' Squibs; Leading and Connecting Wires; Cap Crimpers; Rheostats; 
Galvanometers; Thawing Kettles; Tamping Bags; Blasting Mats; Portable 
Magazines. 



MISCELLANEOUS COMMODITIES 

Du Pont Hand Trap, Charcoal; Wood Pulp, Nitrate of Soda 
-Crude and Refined; Saltpetre; Wood Oil; Recovered Salt. 



MPoE 



111 



PRODUCTS OF THE 
Associated (gJPDNj) Companies 

DU PONT CHEMICAL WORKS 

Equitable Building, New York City 

Laboratories : Parlin and Deepwater Point, N. J. 

Acetic Ether, Amyl Acetate, Aniline Oil, Bronzing Liquids, Collodion, Dark Creosote, 
Dead Oil, Dimetbylaniline, Dinitrdphenol, Ethers, Ethyl Acetate, Flotation Oils, Iso 
Amyl Acetate, C. P., Wood and Metal Lacquers, Leather Renovators, Leather Substitute 
Solutions, Mantle Dips, Naphthalene, Nitre Cake, Nitrobenzoi, Parlodion, Patent and Split 
Leather Solutions, Pegamoid Aluminum Paint, Pitch, PY-R.A-LIN Enamels, Refined 
Acetone Oil, Refined Creosote, Refined Fusel Oil, PONTAR, PONTOKLENE, Salicylic 
Acid, Shingle Oils, Sodium Acetate, Soluble Cotton, Solvent Naphthas and Thinners, 
Special Pyroxylin Solutions, Sulphur Black, Waterproof Cement, Wood and Metal Pre- 
servatives. 

DU PONT FABRIKOID CO. 

Du Pont Building, Wilmington, Del. 

Factories: Newburgh, N. Y.; Fairfield, Conn.; Elizabeth, N. J.; 

Toronto, Ont. 

FABRIKOID is a leather substitute and made in various colors, grains and weights. 
FABRIKOID is used for: Upholstering Furniture, Automobiles, Carriages, Railway 
Coaches and Marine Craft; Bookbindings; Manufacture of Hand Bags, Trunks, Harness, 
Shoes; Auto, Carriage and Boat Tops; Cushions, Gloves, Gun and Instrument Cases; 
Novelties, Millinery, Curtaifis, Screens, Hats and Caps, Hat-Sweats, Sporting and 
Theatrical Garments and Display Fixtures. 

RAYNTITE Top Materials are made in single and double texture fabrics, coated with 
either pyroxylin or Fairfield rubber. RAYNTITE Top Materials are guaranteed one 
year against leakage. 

We manufacture Fairfield Fabrics of rubber surface for Automobiles, Carriage and 
Marine Craft Tops, Hospital Sheeting, Army Blankets, Storm Aprons for Carriages and 
Rug Anchor. Samples sent on request. 

THE ARLINGTON CO. 

725 Broadway, New York City 

Factories : Arlington, N. J. ; Poughkeepsie, N. Y. 

Manufacturers of PY-RA-LIN, a waterproof, flexible, opacjue or transparent material, 

in the form of sheets, tubes, rods and beading, lor making: Toilet and Manicure Articles. 

Novelties, Instrument Keys and Parts, Dials, Optical, Scientific, Surgical and Mechanical 

Instruments, Ofl&ce and Stationery Supplies, Buttons, Buckles, Cutlery Handlen, Aero- 

;^plane Wings and Windshields, Jewelry and Powder Boxes, Name Plates, Picture Frames, 

%&ff'oys, Games and Accessories, Smokers' Articles, Electrical Apparatus, Harness Trim- 

' tnings, Hospital Supplies, and other articles requiring a product of PY-RA-LIN'S 

characteristics. . 

Manufacturers of Specialties and IVORY FY-RA-LIN toilet accessories. 
MAKERS OF CHALLENGE CLEANABLE COLL'^JIS AND CUFFS, having the 
' pelebrfttad "linen finiat-" Ask to see them at your haberdasher's. Ask for style booklet. 
Sample^f any style or size sent for 25c. 



HARRISONS, Inc. 

35th & Grays Ferry Road Philadelphia, Pa. 

Factory : Philadelphia, Pa. 

Ready Mixed and Industrial Paints and Varnishes for all purposes; White Lead, Red 
Lead, Litharge, Colors in Oil. Acetic, Lactic, Nitric, Sulphuric and Muriatic Acids in 
commercial strengths. Crystal Potash Alum, Iron Free Sulphate of Alumina, Barium 
Chloride, Nitre Cake, Nitrite of Soda. 

DESCRIPTIVE BOOKLETS of the products made by the E. I. du Pont 
de Nemours & Co. and its associates are sent FREE upon request. State 
precisely what particular products interest you to enable us to select and send 
the printed matter containing the information desired. 

Address all requests for booklets to Advertising Division, E. I. du Pont de 
Nemours & Co., Wilmington, Del., U. S. A. 



112 



Professional Blasters can find 
Profitable Employment 



We should like to hear from men with blasting experience in 
mines, quarries or with contractors, etc. 

Blasters can obtain profitable employment from land owners 
and fruit growers who have land to clear of stumps and boulders, 
ditches to be dug, ponds and low spots to drain, trees to plant or 
cultivate, roads to mcike, or fields to subsoil. 

Hundreds of men scattered all over the United States are 
making a living by devoting their time to work of this kind, but 
there are not nearly as many men engaged in it as are necessary 
to taJce care of all of the work to be had. 

We do not employ agricultural blasters, but we do 
everything in our power to assist those who take up the work to 
secure blasting jobs from parties in their locality who have replied 
to our extensive advertising. The parties employing them pay 
them for their work. We also give agricultural blasters attractive 
handbills and posters, advertising their business, booklets and other 
printed matter which, when properly distributed and used, assist 
them in securing work. 

Our Agricultural Blasting Booklet tells what successful blast- 
ers are making in this work and describes their methods of 
securing it. 

CUT THIS CARD OUT ALONG THE RULED LINES 

!r'— 



,, BLASTER CARD 

IF YOU WANT TO TAKE UP AGRICULTURAL BLASTING— c6t OUT, 
FILL IN AND MAIL THIS CARD 

E. I. du Pont de Nemouri & Company 
Wilmington, Delaware 

Gentlemen — Please send me your Agricultural Blasting Booklet describing the money-making oppor- 
tunities in the profession and explaining the methods of successful blasters. 



^ Name „ 

Street and No. or R.F.D 

Town State... 



E. I. du Pont de Nemours & Company 

Home Office — Wilmington, Del. 



BRANCH OFFICES: 



BIRMINGHAM, ALA. 
BUFFALO, N. Y. 
CHICAGO, ILL. 
DENVER, COLO. 
DULUTH, MINN. 
HUNTINGTON, W. VA. 
JOPLIN, MO. 
JUNEAU, ALASKA 
KANSAS CITY, MO. 

MEXICO 



NEW YORK, N. Y. 
PITTSBURGH, PA. 
PORTLAND, ORE. 
SAN FRANCISCO, CAL. 
SCRANTON, PA. 
SEATTLE, WASH. 
SPOKANE, WASH. 
SPRINGFIELD, ILL. 
ST. LOUIS, MO. 
CITY, MEX. 




PLACE 

ONE-CENT 

STAMP 

HERE 



MGR. AGRICULTURAL DIVISION 



WILMINGTON. DELAWARE