省农业科学院农业气象研究室和合肥气候站共同研究試制出几种防霜剂。第一种是用硫酸銨(或氯化銨)、干牛粪各一半,加入少量清水,拌合晒干,制成块状,然后放在火爐燃燒,卽可发生濃烟。每亩費用,用硫酸銨的合4—5分錢,用氯化銨的合2—3分錢。第二种 Provincial Academy of Agricultural Sciences Agricultural Meteorology Laboratory and Hefei Climate Station joint research trial developed several anti-frost agents. The first is the use of ammonium sulfate (or ammonium chloride), dry cow dung each half, add a small amount of water, mixing dried together, made of lumps, and then placed in the furnace burning, 卽 smoke can occur. Per acre fee, with 4-5 cents of ammonium sulfate, with 2-3 cents of ammonium chloride. The second one