28 



HARDWOOD RECORD 



May 10, 1921 



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77ie ^^Caterpillar'' Trailer 



IT is interesting to note the progress which has been made dur- 

 ing recent years as a result of the educational advantages and 

 experiences learned from the armies overseas. The war with its 

 terrible cost and its gruesome results has accomplished one impor- 

 tant measure — the rapid progress of mechanical appliances. 



A great deal has been written about the ' ' Track Laying ' ' type 

 tractor, which was originally conceived as an agricultural unit, and 

 was later developed by the military engineers, who realized its 

 advantages as a military weapon. The complete success of tlic 

 tank lead to the adoption of the "Artillery" model tractor, and 

 this was used extensively and with great success in hauling heavy 

 guns and supplies to the front. 



With the return of peace the lessons leurned about tractors dur- 

 ing this great conflict were utilized by the progressive and ever 

 alert hardwood industry. The year of 1919 saw the introduction 

 of the "CATERPILLAR" tractor as an emergency equipment for 

 skidding and hauling logs. These tractors have completely proved 

 their value, primarily because the autumn and winter of 1919 saw 

 an unprecedented amount of rainfall in the south. The woods, 

 which were always difficult to log, became almost impossible. Over 

 night they were turned into an impassable sea of water and mud. 

 Skidding and hauling by oxen and mule teams was practically 

 impossible, and every reader of the Hardwood 

 Record doubtlessly knows the value which these 

 tractors proved to be. 



The one drawback, and obviously an obstacle which 

 had to be overcome, was the trailer question. Al- 

 though it was possililr hi vnU-r the low lands, the 

 swamps and bogs, 

 with the tractor, 

 round wheel trailers 

 mired down and 

 hopelessly buried 

 themselves up to 

 the hub and, in 

 many cases, to the 

 bunks. 



The experiences 

 of the practical 

 1 u m b e rmen, who 

 have operated trae- 

 t o r s successfully 

 under adverse con- 

 ditions and who 



"Clo5e-iip" of a "Caterpillai" Trailer in Action 



have continuously been handicapped by the 

 inability of the wheel trailer to follow the 

 tractor, has lead to the introduction of one of 

 the greatest pieces of equipment ever offered 

 the logging industry, and particularly the hard- 

 wood division. 



The HOLT MANUFACTURING COMPANY of Peoria, 111., has 

 recently announced the completion of the "CATERPILLAR" 

 trailer. All of the manufacturing principles and designing fea- 

 tures which have made this particular make tractor a success in 

 the woods are incorporated in the construction of this trailer. 

 This trailer has shown the following general specifications: 



MAIN FRAME: Structural steel, hot riveted, laterally braced. 

 TRUCKS: One truck on each side, free oscillating type, carried 

 on tubular axle; no spring mounting. 



TRUCK WHEELS: Three in each truck, chilled grey iron, 

 equipped with Hyatt Roller Bearings. 



TRACK IDLERS: Two on each truck, all interchangeable, 

 flanged type, rear mounted rigid to truck frame and the front 

 adjustable. Equipped with Hyatt Roller Bearings. 

 TRACK: Cast steel link, 11" wide, solid type. 

 BODY: To be furnished by customer. 



GENERAL DIMENSIONS: Maximum overall length, 13' 4"; 

 maximuni overall width, 79"; maximum overall height, 27"; cen- 

 ter line to center line of tracks, 62"; width of track, 11"; ground 

 clearance, 14"; height of drawbar from ground, 17"; length of 

 ground contact, 48"; ground pressure per square inch, when loaded, 

 12.5 sq. in.; carrying capacity, from 3 to 5 tons; weight of trailer, 

 3,340 pounds. 



The editor of this department believes 

 the introduction of this trailer will fill a 

 long felt want in 

 every logging camp. 

 This is particularly 

 true in such cases 

 where operations 

 are to a great ex- 

 tent confined to low 

 lands. 



Without regard to 

 the value of this 

 new trailer, it is 

 most interesting to 

 sec the reasons and 

 the causes which 

 have lead to its de- 

 velo])ment. First, 

 the experiences of 

 the ,inuy officers in 

 the " F 1 :i n d r s 



