517 
commercial paste form is more convenient, the quantities used de- 
pending on the particular brand, as these contain more or less 
moisture. Of Swift’s brand, which is generally stocked, 2lbs. are 
mixed to each 50 gallons of water. 
Paris Green is another arsenical poison much used. It is a 
chemical combination of arsenic and copper. When unadulterated 
it contains 55 to 60 per cent. of arsenic. It is almost insoluble in 
water. It is applied either—Ist, dry in a state of impalpable 
powder, mixed in the proportion of loz. of Paris green with 2lbs. 
tlour, slaked lime, road-dust, or ashes; 2nd, or in ‘a liquid mixture 
in the proportion of loz. in 10 gallons of water. It should not be 
used in conjunction with any acid substance which would dissolve 
the arsenic it contains and make it caustic, but, on the contrary, 
it is always a good plan to add to it a handfal at lime, which has 
the property of turning insoluble any trace of caustic arsenic it 
contains. Being a heavy substance, it quickly settles to the bot- 
tom of the pumping tackle, and requires agitating. A little glue or 
flour paste may be added, to cause it to adhere better, especially 
to plants with glossy leaves. 
Hellebore, unlike the arsenites, which are mineral poisons, is 
a vegetable poison, and is less dangerous. It is a powder made of 
the roots of the white hellebore, and kills both by contact and by 
being eaten. Very effective when fresh, it loses its strength by 
standing. In doses loz. to three gallons of water it is much used 
against the pear slug and leaf-eating worms. 
Pyrethrum, or Insectibane, is also a poison, and is effective 
when fresh, but loses strength when exposed to the air. It is made 
from the powdered flowers of plants of the genus Pyrethrum. That 
light-brown powder is dusted over the plants or sprayed, in the pro- 
portion of Pyrethrum one tablespoonful, boiling water two gallons. 
It kills by contact, and should be applied as long as the insects 
persist. Burnt over hot coals in the conservatories and greenhouses, 
it rids plants of aphis and other insect pests. Pyrethum are easily 
cultivated, make pretty borders, and a supply of fresh flowers could, 
without trouble, be raised in every garden. 
Kerosene, in the form of an emulsion with soapsuds, or 
mechanically mixed with water in the form of a misty spray, in the 
proportion of one of kerosene and four of water, will kill nearly all 
insects, and not injure the foliage. 
Resin Compound is known to be very effective against scale 
insects. One of the best formulas is: caustic soda, one pound: 
resin, five pounds; water, 25 gallons. Two ounces of Paris green 
may be added to this when used. 
Sal Ammomac (chloride of ammonia) at the rate of 34 to loz. 
per gallon of water, is a cheap and efficacious spray against red 
seale, 
