180 



Department U. S. A., Congressional Library, "Wisconsin 

 Historical Society, and a Committee of the Boston Society 

 of Civil Engineers. 



Mr. Chase described a Japanese translation of Dr. Henry 

 Hartshorne's book entitled, " Essentials of the Practice of 

 Medicine." 



Mr. Price exhibited a piece of wood, very dry and light, 

 and not at all mineralized, recently obtained from a city 

 well, and desired to place on record the following memo- 

 randum : 



Two wells for drains have been dug at and near the southern end of the 

 Hotel at the southwest corner of Broad and Walnut streets, the highest 

 part of the old city of two square miles in area. After the surface and 

 brick claj% the digging was through firm blue clay to the depth of thirteen 

 feet from the curb line ; then fine gravel ; and at the bottom coarse " water 

 gravel," which was penetrated to the depth of 27 feet from the curb, where 

 the digging ceased, without going below that gravel. The lower was the 

 coarsest, with pebbles two or three inches in diameter; and through it were 

 scattered some unrounded stones, with angles more or less sharp, but only 

 a few inches in length, and the largest not over eight inches long. Near 

 the bottom was found the limb of a tree, two inches thick in the broadest 

 diameter. 



Mr. Blodget described the clays and gravels underlying 

 the city, and a map of Broad street, from South street to 

 League Island, which he had published to show that they 

 were evenly deposited at about the level of tide. 



Mr. Blodget said that, in the borings on League Island which he super- 

 intended, the gravel beneath the clay was proved to pass under the water 

 and forms the river bed, allbrding good holding ground for ships every- 

 where, the central channel being 33 feet deep, and the inshore soundings 

 16 feet below low water mark. A little mud is seen at the upper end of 

 the island. The southern end shows a tough clay, which sets or hardens 

 on exjiosure, and is used for eml«,nking. At Point Breeze, in excavations 

 for the large bank, one foot of quicksand was found 45 feet down, under 

 which lay firm gravel ; the series from the surface downward being 1, top 

 Ipam ; 2, sandy clay and blue clay ; 3, gravel. Piles 18 feet long driven 

 through blue clay took firm hold in the lower gravel. 



Mr Tathem said that at Fiftli and Walnut streets there were two gravels, 

 separated by 20 feet of blue clay and mud, a pure slimy blue clay without 

 a particle of gravel. 



Morris, Tasker & Co. 'swell in Southwark went down 70 feet before 

 striking rock, and contiiaued in the rock to a deptli of 250 feet. 



Mr. Price said that his present excavations at Twenty-eighth and Oxford 



