PROCEEDINGS OF THE POLYTECHNIC ASSOCIATION. 537 



Mr. Dibben remarked on the known effect of salt on snow and 

 ice, whether with or without water. As the water is added to 

 the mixture by the thawing of the snow, the temperature at which 

 it will remain fluid is higher. Salt and snow alone will sink to 

 8 deg. F., or 8 deg. below zero. As the snow melts and the 

 brine freshens, it ceases to melt more snow at 28 deg. or 29 deg. 

 The occurrence on the 8th February, 18G1, Mr. D. thought was 

 due in part to th(! salt remaining on the track, which increased 

 the evil of the sudden cold weather and slight fall of snow. Mr. 

 D. thought the increased cold due to the salting of the railroad 

 was very sensible to the human feet; he could distinguish it 

 readily himself, and he thought its effect was evil. 



It was an universal opinion, and he thought a correct one, 

 that distempers in the feet of horses, other than railroad horses, 

 occurred in an increased degree after each salted snow. 



Mr. Ebbitt thought Mr. Dibben more sensitive to the tempe- 

 rature than most people, and that most persons with their feet 

 ordinarily clothed would not experience any sensation whatever 

 in crossing a salted and briny track. He had 7iever had any fros- 

 ted feet among his horses, although salting for several years, 

 except that period in February, 1861. 



Mr. Robert Walker thought the horses were of less account 

 than human beings. The water produced by salting the track 

 was muddy and slimy, and would always wet the boots of the 

 gentleman crossing, and worse, the morocco of the ladies' balmo- 

 rals. It penetrates both, and the common council had a view to 

 the health of the foot travelers mainly. The fact that salt was 

 good in the food, and was in the blood, etc., did not show that 

 salt in water did not prevent wet feet from injuring health. 

 Working girls had to work all day with the feet wet, occasioned 

 by crossing the salted railroads. The salt was a great injury to 

 such persons, and to all others who have to walk through it, or 

 even upon the sidewalks near the crossings. 



Samuel Hotaling said he was the first to call the attention of 

 the authorities to the use of salt to thaw out hydrants and the 

 like. He was a dealer in salt, and had been familiar with the 

 provision business since boyhood. He had walked through salt 

 slush every winter and through brine in summer. It was not 

 injurious; it was a healthy business. During the yellow fever iu 

 this city, when the people left the lower part of the city, they 

 flocked to a packing-house yard to avoid contagion. 



