SCIENCE AND INDUSTRY. 
parts of liquid squill and milk; the rats being thus made to partake 
of more poison in their efforts at relief. 
Squill may be obtained either in the form of a powder or of a 
solution. -Although comparatively harmless to domestic animals, it is 
extremely toxic as far as rats are concerned, the minimum lethal dose 
being only half a grain. Mix the powdered squill with tallow or drip- 
ping, or with either of these fats and oatmeal. The mixture should 
be smeared on bread, the latter being then cut into small pieces. In 
the liquid form squill may be prepared for use in the following manner: 
—Mix equal parts of liquid squill and milk, and to each pint of the 
solution add 1 lb. by weight of bread. 
Of all rat poisons, squill solution is believed to be the most effective, 
and has been recommended in preference to barium carbonate for the 
following reasons :— 
(a) It is three times as toxic for rodents. 
(b) It is even less harmful to most domestic animals, The one 
point against the use of squill, however, lies in the fact 
that at present it is somewhat more expensive than most 
- other poisons. 
There is always a possibility of a rat dying under flooring or behind 
wainscoting, either through poison or otherwise. If a rat from a drain 
takes poison, and cannot regain its habitation, the carcass will most 
probably become putrid. If such a rat dies near a fireplace or hot-water 
pipe, the stench will be intensified. Chloride of zinc is a good deodorizer 
in such cases, and combines with and neutralizes the offensive chemical 
products of putrefaction. If necessary, a hole should be bored with a 
bit and brace in the vicinity of the supposed source of origin of the 
odour if possible. Some perfume or pinewood oil can be added to the 
~ zine chloride, which should be applied through the hole. A cork will 
close the orifice, and can be withdrawn from time to time to ascertain 
whether the nuisance has abated. Where possible, however, it is advis- 
able to remove the carcass immediately its presence has been detected. 
G-ASSING. 
Of all the methods advocated, gassing, under certain conditions, is 
the quickest and most certain for destroying rats on a large scale. 
When employed in buildings or other places where the runs are not easy 
of access, gassing has the advantage over all others in that it kills not 
only the adults, but also the young or newly-born in their nests. The 
most suitable gas to employ, and the one recommended, is sulphur 
dioxide. 
Sulphur diowide is a heavy gas, and may be prepared by burning 
-sulphur in air or oxygen. It is non-inflammable, and has a pungent, 
suffocating odour. It is comparatively cheap to prepare, and is quite 
harmless to man and the domestic animals when inhaled in small quan- 
tities. When sulphur dioxide gas is driven into rat holes under pressure, 
the whole network of runs is permeated in a few seconds, making the 
existence of the rats underground impossible. Although many of the 
rodents escape only to die in the open, some, no doubt, recover. “The gas 
kills many of the rats by immediate suffocation, whilst those that escape ~ 
into the open die from acute congestion of the lungs, To secure rats 
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