Make 30 of these knots and then push them off the stick and proceed in the same way with the next row, passing the needle first through each of the 30 knots made for the first row.  Make 30 rows and then tie the last loops to the other iron ring.  Stretchers may be made and put in place and the hammock, strong and durable, is finished.  The work must be carefully and evenly done.  One is apt to have a little trouble getting the first row right, but after that the work proceeds quite rapidly.

How to Obtain Cheap Dry Batteries [410]

Not very many people realize that good, serviceable dry cells can be obtained from an automobile garage very cheap.  These cells having been “run out” beyond the required number of amperes for automobile use, will give excellent service, considering their cost.  Many of them will give two-thirds of their original amperage.  Six of such cells have been in use on my door-bell circuit for nearly a year.  They can be used for other purposes just as well.  —­Contributed by H. H. Cutter.

** How to Make a Water Telescope [410]

[Illustration:  The Water Telescope]

Before you decide on a place to cast your hook it is best to look into the water to see whether any fish are there.  Yes, certainly, you can look into the water and see the fish that are there swimming about, if you have the proper equipment.  What you need is a water telescope.  This is a device made of wood or metal with one end of glass.  When the glass end is submerged, by looking in at the open end, objects in the water are made plainly visible to a considerable depth.  In Norway, the fishermen use the water telescope regularly in searching for herring shoals or cod.

All that is necessary to make a wooden water telescope is a long wooden box, a piece of glass for one

[Illustration:  Wooden Water Telescope]

end and some paint and putty for making the seams watertight.  Fix the glass in one end of the box, and leave the other open to look through.

A tin water telescope is more convenient than the wooden one, but more difficult to make, The principal essential for this is a circular piece of glass for the large end.  A funnel shaped tin horn will do for the rest.  Solder in the glass at the large end and the telescope is made.  Sinkers consisting of strips of lead should be soldered on near the bottom to counteract the buoyancy of the air contained in the watertight funnel and also helps to submerge the big end.  The inside of the funnel should be painted black to prevent the light from being reflected on the bright surface of the tin.  If difficulty is found in obtaining a circular piece of glass, the bottom may be made square and square glass used.  Use plain, clear glass; not magnifying glass.  To picnic parties the water telescope is of great amusement, revealing numerous odd sights in the water which many have never seen before.

** How to Rid Your Yard of Cats [411]