TESTS OF PHILIPPINE KOAD MATERIALS. 461 



results was made to the Director of Public Works, accompanied by an 

 offer to test a series of samples of crushed stone from the quarries operated 

 iu the provinces. In accordance with this offer, a number of samples 

 have been received and tested, and their percentage of wear ^Adll be found 

 recorded in the table in the first part of this report. It has not been 

 possible as yet to do any field work to determine whether the quarries 

 which are operated are supplying the best rock which can be obtained, but 

 it will be noticed that there is a wide divergence in the character of the 

 stone used, and in some cases the percentage of wear is so excessive that 

 if any better stone could be obtained, even at some additional cost, the 

 roads might be improved and the expenses would perhaps be counter- 

 balanced by the saving in maintenance. It is the desire of the Bureau 

 of Science to aid as fully as possible in the economic problem of the use 

 of road materials and it is hoped that further tests, and possibly some 

 field work, may be carried on each year in cooperation with the Bureau 

 of Public Works. It is planned to equip a laboratory with all the stand- 

 and machines so that complete tests may be made. The necessary ap- 

 paratus for this has already been ordered. 



