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The National Geographic Magazine 



which the road is to be constructed is to 

 be clinkered, but only a sufficient amount 

 should be rendered non-plastic to neu- 

 tralize the too sticky character of the na- 

 tive clay. Fortunately the gumbo dis- 

 trict is plentifully covered with heavy 

 timber, thus affording an abundance of 

 fuel. 



While the only experimental burnt- 

 clay road constructed by the office was in 

 Mississippi, the same methods might be 

 applied with equally good results in the 

 sections of the prairie states that have no 

 other material available for road build- 

 ing- 



It is, of course, impossible to give the 



cost of a burnt-clay road whicn will apply 

 to the same work in all sections of the 

 country. The items of cost of the ex- 

 perimental road 300 feet long, as con- 

 structed at Clarksdale, Mississippi, are as 

 follows : 



30^2 cords of wood at $1.30 per cord. . $39-65 



20 loads of bark, chips, etc 6.00 



Labor at $1.25 per day and teams at $3 



per day 38.30 



Total cost of 300 feet . '. 83.95 



Total cost per mile at this rate. . .1,478.40 



In view of the success of the experi- 

 ments so far made and the comparative 

 cheapness of this form of construction, it 

 is hoped that the localities which have no 

 hard material available will continue the 

 experiments with burnt clay. Although 

 it cannot be denied that the gumbo and 

 buckshot clays of the South are partic- 

 ularly adapted for burning on account of 

 the high percentage of organic matter 

 which they contain, it is none the less 

 probable that many of the surface clays 

 and soils of the states farther north could 

 be treated in the same way, and in fact 

 any soil or clay which bricks or clinkers 

 at a comparatively low temperature 

 should be suitable for the work. 



Since the experiment made by this of- 

 fice at Clarksdale, Mississippi, numerous 

 sections of burnt-clay road have been 

 built in that locality, and up to the pres- 

 ent time only favorable reports regarding 

 them have been received. 



THE WORK ON THE ISTHMUS 



IN spite of the rainy season, which ex- 

 tends from the end of April to the 

 end of December, steady progress has 

 been made in all branches of the work 

 on the Isthmus during the past three 

 months, or since Congress in June last 

 decided definitely upon the type of canal. 

 Until that decision was reached many 

 lines of work were held in suspense. It 

 was impossible, for example, to fix the 

 location of dumps until it should be 

 known what kind of canal was to be con- 

 structed. From the moment the decision 

 was reached the chief engineer set the 

 work in motion along all lines of activity, 

 and the results achieved show very 

 clearly in the statistics which he has 

 since sent to the Commission at Wash- 

 ington in his monthly reports. 



The amount of excavation in the Cule- 

 bra Cut during August was about 245,000 

 cubic yards, which exceeded by 5,000 

 cubic yards all previous monthly records. 

 The amount for September was about 

 289,000 cubic yards, or 50,000 greater 

 than the largest previous record. 



There was available at the end of Au- 

 gust a total force of 46 steam shovels, of 

 which 27 were at work in the canal 

 prism, 2 outside of the prism, 4 on the 

 Panama Railway, and the rest set up and 

 ready for work in various places. 



The double tracking of the Panama 

 Railroad, which is of vital importance to 

 the removal of spoil from the Cut, is 

 going forward steadily. Of the 35 miles 

 of additional track contemplated, about 

 15 miles have been completed and are 

 ready for use, and about 10 miles more 

 are ready for track laying and ballasting, 

 or about 75 per cent completed. 



The receiving and forwarding yards 

 on both sides of the Cut, which are to 

 serve as great clearing houses for trains 

 of spoil from the Cut, are practically 

 completed at Pedro Miguel and Las Cas- 

 cadas, and the yard at La Boca is about 

 75 per cent completed. 



The great difficulty with labor has 

 been somewhat overcome by slight im- 

 provement in the quality of the work of 



