75 



was unwilling to have a pit sunk there, as he cultivated the field, and 

 had a crop of potatoes growing on it at the time. 



We left ]Mr. Higgins to make the proper arrangements for the ex- 

 plorations called for, and to obtain from the Brandon Iron Company 

 some miners, to whom the excavation could be safely intrusted. 



Mr. Blake visited the works from time to time, as his ad-vice was 

 needed. 



The first pit was sunk in the garden, seventy feet south-east of the 

 frozen well, to the depth of twenty-nine feet. The strata were found 

 to be clay and sand near the surface, and the lower part consisted of 

 gravel and boulders. No frozen strata were found. After examining 

 the results of this digging, we decided to make an opening west of the 

 well, and Messrs. Blake and Higgins obtained permission of the se- 

 lectmen of Brandon to sink a pit on the roadside. This was found to 

 be very difficult ground to excavate, requiring much skill on the part 

 of the miners to prevent accidents from falling in of the walls Of the 

 pit ; double timbering and planking being needed to support the walls. 



This excavation gave more satisfactory results ; for the moment the 

 gravel and boulder bed were struck, they were found to be very cold, 

 and near the bottom of the bed frozen earth was found. This was in 

 the month of October, when the summer heat had penetrated as far 

 as possible into the earth. We chose that time expressly for the 

 purpose of ascertaining whether the surface heat ever reached the 

 bottom of this frozen bed. 



July 2d, 1861. — Messrs. Blake and Jackson revisited Brandon and 

 re-examined the frozen well and the pit which had been dug by the 

 roadside. 



The temperature of the water in the well was found to be 33° 

 Fah., and that of the air around 62° Fah. A rim of ice, three feet 

 above the liquid water in the well, and one foot in thickness, then 

 existed, attached firmly to its walls. The bottom of the well feels, by 

 the sounding-lead, as if it was covered with solid ice ; but we could 

 not obtain any from the bottom, owing to the want of suitable tools 

 for breaking it up, but gave directions to have the fact ascertained 

 under Mr. Higgins's superintendence. 



We sent the miners down into the pit which they had sunk and 

 covered up carefully with shavings, to prevent alteration of tempera- 

 ture, and had the pit re-opened, and the bottom dug into. A ther- 

 mometer, in its tin case filled with water, was buried in the cold 

 earth at the bottom of the pit, and allowed to remain some hours, 

 after which it was tak^'h out, and the temperature was found to be 

 42j-^Q-° Fah. This stratum when first dug into was frozen ; hence 

 the summer heat had penetrated to some extent since the shaft was 

 sunk, in spite of all the precautions which had been taken to pre- 

 vent it. 



