798 



THE IRKIGATION AGE. 



What Mr. Campbell Says 



You know Mr. Campbell, either personally or by reputation. There 

 is no better authority in the United States on grain growing. He is 

 the father of "dry farming," and an expert on soil preparation and 

 seeding. 



One of his subscribers wrote and asked him what kind of a drill to 

 buy. He replied as follows through the columns of his paper, Camp- 

 bell's Scientific Farmer, Lincoln, Nebraska: 



"The question of advice regarding the kind of a drill is a rather 

 delicate affair. It is a question we do not like to discuss in detail. 

 We have had considerable experience with the different kinds of drills. 

 Our early favorite drill was the closed heel shoe drill. 



"While this shoe drill deposited the seed in an ideal condition when 

 the soil was perfect, yet there were a number of objections to the 

 construction. First, the draft of the machine was too heavy. It took 

 four good horses to handle an eight-foot machine. Second, if there 

 were any corn stalks or other obstructions in the soil, it would force the 

 shoe out of the ground, thus causing an uneven depth of seeding. 



"The double disc overcomes the two difficulties above mentioned. 

 This is especially true of the Monitor drill, as it is made with two 

 straight coulters, coming together in front, thus permitting the estab- 

 lishing of the same V-shaped crevice in the solid soil. In other words, 

 there is no loosening of the soil, the tendency being to pack the bottom 

 and both sides. Because of the rotating motion of these discs, the 

 friction is materially reduced. We have two of these drills in use 

 twelve feet in width and four fairly good horses handle them with ease. 



"The real point to be considered in a drill is that of depositing the 

 seed in a manner that quick germination may be promoted, followed by 

 rapid and prolific development of roots. Those who have followed us 

 through numerous articles on the preparation of the soil must begin to 

 appreciate that very much depends upon the condition of the ground 

 where the seed is deposited. Not only with reference to the quick 

 germination of the seed, but that of a continued strong, healthy growth 

 of the plant to maturity. Just a thought upon this point should con- 

 vince the farmer that there is some virtue in the drill we are referring 

 to, for after spending much time and effort to get a fine firm seed bed, 

 it would be unwise to use a drill that would again loosen up qyite a 

 portion of this." 



If there has been any doubt in your mind on the drill question the 

 above editorial should remove it. Mr. Campbell has carried on his 

 experiments in nearly every state west of the great lakes. There is no 

 style of drill that he has not tested, he knows what he is talking about 

 and is not afraid to use the columns of his paper to pass the word along 

 for the benefit of the farmers, in^ whose interests he has devoted his 

 talents and the best years of his life. 



The Increase in Yield on Fifty Acres will 

 Pay for the Drill 



The Monitor 13 approximately one-third lighter draft than any 

 other machine of equal capacity. It will work where any other drill 

 will work, and often under conditions where no other drill can work. 



It is the only drill that puts all the seed at the bottom of a clean, 

 wide furrow, in two rows, at an even depth, and covers with a uniform 

 amount of earth, by reason of which 



It requires one-fifth less seed than other machines it all grows, 

 no waste. 



It increases the yield of wheat usually from three to seven bushels 

 per acre. Other grains in proportion. 



Wheat grown from seed sown by it will grade higher and consequently 

 bring a higher price. 



We have never yet been able to manufacture enough of these drills 

 to fill all orders. If your dealer has none on hand he can get one for 

 you now if he hustles. 



MOLINE PLOW COMPANY 



MOLINE, ILLINOIS 



Makers of the Famous Mollie Plows and Other Flying Dutchman Firm Tools 

 Maidt Wagons and Bob Sleds. Kenner Biaies. Light Donning National and 

 Mandt Manure Spreaders, Freeoort Carriage Co. Vehicles and Monitor Drisll 



Fig. SO. 



(Continued from Page 782.) 



6. Similarity. 



Triangles are similar when the angles in the one triangle 

 arc respectively equal to the angles in the other triangle. 

 In Fig. 29 the line DE is drawn parallel to 

 BC, then angle d = angle b, and angle e = 

 angle c, and the angle a is as well in the triangle 

 ADE as in triangle ABC; so the triangle ADE is 

 <" similar to triangle ABC, and the sides in the 

 Fig. 29. one triangle are proportional to the sides in the 

 other which gives the proportions : 

 AD : AB = AE : AC; also, 

 AD :DE = AB : BC; also, 

 AE : DE AC : B'C, etc. 



In picking out the proportional pieces care must be taken 

 that it is done correctly, i. e., that the pieces are similarly 

 placed, so if AD is picked as the first antecedent and DE 

 as the first consequent, then the second antecedent must be 

 similar located in the other triangle ; AD lies opposite the 

 angle e and angle e = angle c, so the line opposite angle c 

 corresponds to AD ; this is AB ; likewise, the first consequent 

 DE lies opposite angle a ; hence, the second consequent must 

 have the same position in the other triangle which points to 

 line BC lying opposite the same angle. 



7. Mean Proportionality. 



When in a proportion the two middle terms are equal it 

 is called a mean proportion, for instance : 



a : b = b : c, 



which by forming the products of means and extremes gives 

 the equation. 



b" = ac. 



This principle is demonstrated in a right 

 angle d triangle ABC, Fig. 30, in which the 

 line BD is drawn perpendicular from the 

 right angled corner to the Hypothenuse ; then 

 there are three similar triangles ; triangles 

 ABC and ABD are similar; hence the sides 

 are proportional ; let AB = a, BC = b, and AD = c, DC = 

 d, and BD = h', then : c + d : = a' = a : c; also c + d 

 :b = b : d. This means that the perpendicular from the 

 right angle of a right angle triangle to the Hypothenuse di- 

 vides it so that each of the other two sides is a mean propor- 

 tional between the adjacent segment of the Hypothenuse and 

 the Hypothenuse. 



Also, triangle ABD is similar to triangle BCD, then 

 a : b = c : d, and this shows that the perpendicular drawn 

 from the right angle to the Hypothenuse divides the Hypothe- 

 nuse proportional to the two adjacent sides. 



The first principle proves also the forty-seventh problem 

 of Euclid, that the square of the Hypothenuse is equal to the 

 sum of the squares of the other two sides as follows : 



Form the product of the means and extremes : 



a" = c (c + d). 



tf = d (c + d). 



Add these two equations together : 



a* + b 2 = (c + d) (c + d) = (c + d 2 ); 

 but c + d is the Hypothenuse. 



As an example let AB = 4 ft., BC = 3 ft., and AC = 5 

 ft, then c and d can be found from the proportion : 



4 : c = 3 : 5 c, or 

 form the product of the means and extremes : 



3c = 4 ( 5 c). 



He = 20 4r. Add 4c on both sides : 



7c = 20. Divide both sides by 7: 



c = 2.857 ft. 

 then d = 5 2.857 = 2.143 ft. 



To find the height BD = h use the proportion : 



/; : 4 2.143 : 3. 



3/1 = 8.572. 



h = 2.857 ft. 



To change the decimal fraction of the feet into inches, 

 multiply by 12; thus: 12 X -857 = 10.28 inches. To change 

 the decimal fraction of inches into the nearest 32nd of an 

 inch, proceed as follows : Subtract 1 from the nearest 1/100, 

 if fraction lies between 12/100 and 37/100; subtract 2 if frac- 

 tion lies between 38/100 and 63/100; subtract 3 if fraction 

 lies between 63/100 and 87/100. and subtract 4 when the frac- 

 tion lies between 88/100 and 100/100 ; then divide by 3 and 

 the nearest number in the quotient will be the answer in 

 32nds; thus, to change the 28/100 inches above into the near- 

 (Continued on Page 801.) 



