496 TRANSACTioys of the American Institute. 



ing ice artificially, and as near as possible adapted to the wants of 

 individuals and families. 



Prof. Jas. A. Whitney. — As yet, the art of producing cold for ice 

 manufacture is not so popularized as to be adapted to the wants of an 

 isolated Virginia planter. But it soon will l)e. Ammonia is the 

 older chemical employed ; of late a subtile product of coal oil, called 

 chimogene, is found cheaper and equally effective. By pressure it is 

 made liquid, and then, when passing into gas, intense cold is pro- 

 duced, because the gas takes up vastly more heat than the liquid, A 

 machine might be made for fifty dollars, which, by a double-lever 

 pump worked fifteen minutes, would condense enough of this sub- 

 stance to cool a dining-room from ninety to seventy degrees, and 

 make abundance of ice for dinner." To which we may add that an 

 apparatus of the sort alluded to will be on exhibition at the Institute 

 fair this fall, and we may take occasion, at the proper time, to give 

 some description thereof. 



Remedy fok Peak Blight. 



Mr. Chas. Frank, Chautauqua county, N. Y. — I have an orchard 

 of standard pears that are generally affected with the blight, tops 

 dying ; the substance that runs from the diseased limbs is like tar. 

 What ails them, and what shall I do ? 



Mr. P. T. Quiun. — Cut off the dead or injured parts of the trees at 

 once, six or eight inches below where the disease shows itself on the 

 branches. Destroy the portion removed by burning. AVhen cutting 

 off large branches at this reason of the year, cover the wound with a 

 paste made by dissolving gum shellac with alcohol or with a coating of 

 ordinary grafting wax. In case the injured trees are disfigured they 

 may be made symmetrical by putting in grafts in the spring, when 

 the branches are large enough. I have saved valuable pear trees, 

 that were badly injured by fire blight, by following this course. 



A Cuke fok Bloat ok IIoven. 

 Mr. Paul Miller, Columbus, Wis. — I wish to contribute an easy 

 remedy for a disease or accident which has been very common thi& 

 summer. I used to be a Cheshire, England, dairyman twenty years 

 ago, and had a stock of nearly 100 cattle. Growing many acres of 

 turnij)s, choking of the cows was very frequent, and the simple 

 remedy was a stick about a foot long and an inch and a half square 

 put in the mouth as a bridle bit ; a string from each end to each horn 



