100 



Concerning the "Pile Co\'ering" the following information was given: 



"The material used by us is a heavy jute burlap, weighing either 10 or 

 15 oz. to the yard, 33 in. wide, according to tlie engineer's specifications — the 

 heavier weight being that preferably used. This is saturated and coated 

 with a specially prepared asphalt and backed with saturated felt. The 

 hea\y grade pile co%ering weighs about 60 poiuids to the 100 square teet, while 

 the lighter weighs about 45 poiuids to the 100 scjuare ieet." 



The exact nature and composition of the jiaint and the asphalt are, quite natur- 

 ally, not given. The asphalt is understood to l)e applied to the burlap cold. 



During 1920, 252 piles were co\'ered by the Parafifine Paint method by the North- 

 western Pacific Railroad for use in the renewal of trestle approaches to the drawbridge 

 over Petaluma Creek at Black Point. The length of these piles ranged from 75 to 107 



Fig. 37. (1) Piling prolucUuii Ijuing appla-d, I'draftine Paint method. N. W. P. R. R., 1920. 

 (2) Pile originally protected by paint, felt and battens, destroyed by Limnoria. 



