[D8736AEO], Letter from John William Lieb, Societa Generale Italiana di Elettricita to Edison Machine Works, November 16th, 1887


View document with UniversalViewer   → View document on Archive.org  → Re-use this digital object via a IIIF manifest


[D8736AEO], Letter from John William Lieb, Societa Generale Italiana di Elettricita to Edison Machine Works, November 16th, 1887

Editor's Notes

"Your favor of Nov. 2nd. is at hand, and I take not eof your observation. ## The past Spring we have had some trouble with contacts in our underground network and as a result of numerous excavations made in different parts of the district we found that the Tubes, both Feeders and Mains were in as horrible condition. In several places the Tubes had entirely disappeared leaving only a covering of rust. We have dug up the streets wherever we had down Tubes and have applied to all our Tubes, Mains as well as Feeders, a very efficient protection. We surrounded the Tubes with tarred and chared wooden castings and between the casings and the Tubes poured in a mixture of 2 parts find sand and 1 part of Tar. The Tar was specially refined so as to contain absolutely no trace of acids or ammonia. In the case of the Feeders already having a high insulation Ressitance this process has quadrupled their insulation. The sand and Tar makes as asphaltic mass as hard and resistant as stone and will preserve the Tubes forever. ## The job cost our Company between 30,000 and 40,000 frames, but it was necessary to protect the Tubes or else shut down the Station ## We took out over 40 lengths of #4 Tubes that were eaten through and over 20 lengths of #1 1/2 and #2 Feeders. The soil in Milan is very bad and iron pipes will not last over three or four years at the most. All the Tubes put down within the last two years were protected by this asphalt composition and they are as good as when laid down. ## Mess. Callender have established an Italian Agency for their Cables in Milan but there is little likelyhood of their doin any business ## We laid down a Feeder recently using Siemens Cable of 650 sq.m/m section and in lengths of 100 meters. This cable laid down with a total conductor length of 5/8 mile, had an insulation Resistance of 29,300 megohms. ## These Cables cost us considerably less than Edison Tubes, about 15% less, and need no additional protection. Our Company formerly paid 6 francs per 100 chilos, customs duty, but a recent decision of the Ministry of Finance raises the duty of 30 fr. per 100 chilos The Tubes were formerly entered as parts of machinery, whereas they are now classed with 'Cables'. ## This change makes a considerable increase to us in the cost of Tubes and makes the Siemens Cable considerably cheaper as Feeders."




Folder/Volume ID


Microfilm ID


Document ID



Thomas A. Edison Papers, School of Arts and Sciences, Rutgers University
Download CSV | JSON