440 TRANSACTIONS OF THE AMERICAN INSTITUTE. 



84 per cent, of fibre, 6^ per cent, of gluten, which may be used like tupicca 

 as food, and 9^ per cent, of herbaceous elements and water. The fibre is 

 not attacked by insects. Its average length is nearly five feet, and the 

 cost of preparation about 42 cents per cwt. 



New Discovery in Pompeii. 



Recent excavations have brought to light a square block of marble near 

 the Isis gate, on tfee sides of which the Roman calendar is engraved. Each 

 side contains the days of three months in three columns, above wliich are 

 the zodiacal sfgns. Interesting and important notices are- placed opposite 

 certain days, relating to astronomy, agriculture and the religion of the 

 Romans. It has been placed in the museum of Naples. 



Ancient Mining Machinery. 



An ancient wheel found in a Portugese mine has been recently exhibited 

 to the antiquarians of Paris. It is 20 feet in diameter and 1| broad. Eight 

 of these wheels have been discovered in mines supposed to have been 

 worked by tiie Romans at least 1450 years ago. They have been preserved 

 by immersion in water charged with salts of iron and copper. They are 

 supposed to have been worked as treadmills by men with naked feet on one 

 side. The water was raised by one wheel into a basin, from which it was 

 elevated another stage by a second wheel, and so on through eight levels, 



Mr. Whittell said the old method for lifting water from the river Nile for 

 irrigation was by means of pots fastened to the arms of a wheel. 



Mr. Bartlett said the v-'ater was raised from Lake Michigan for'supply- 

 iijg the summit level of the Illinois canal leading from Chicago to the M s 

 sissippi river, by means of buckets on a breast wheel. Water can be raised 

 economically in this way six or eight feet. 



Steam Power in Mines. 



In the celebrated Gould and Curry mine steam generated in a boiler on 

 the outside is carried 400 feet below the surface, and 1,100 feet to the 

 engine. The steam pipe is carried along the bottom of the adit iii a v/ooden 

 case tightly packed with'ashes. The difference in the pressure of the steam 

 at the boiler and at the engine is only five pounds per square inch.* At the 

 Almadan silver mine the steam is carried along the roof of the mine in pipes 

 protected by ropes of straw for the distance of 1,300 feet, and with a loss 

 in pressure of 14 pounds per square inch. At the Gould and Cin-ry mine 

 superheated steam is soon to be used. The steam, pipes are provided at 

 certain intervals with expansion joints, like those of the telescope, to pro- 

 ■ vide for the contraction and expansion of the nictals resulting from changes 

 in temperature. 



Dr. Rowell stated steam on the Great Eastern was carried some three hun- 

 dred feet to drive the propellor, the pipe conveying it was at first about 

 two feet in diameter, but it did not work well, and pipe wf.s iiArroased to 

 three feet in order to maintain the original pressure. 



Mr. Stetson said in our Crystal Palace steam was carried across 42d 

 street in a ten inch pipe enclosed in a box filled with tan. It was found 



