SCIENCE SIFTINGS

New Zealand Tablet, Volume L, Issue 11, 15 March 1923, Page 54

SCIENCE SIFTINGS

By VOLT’

Saving Lives with Seaweed.

Hitherto (says Tit-Bits, London) many of us have regarded that common marine plant, the seaweed, as valuable only as a manure, our farmers having used it as such for generations.

Now the scientist has shown us the many wonderful products which can be made from seaweed. In Scotland iodine is being successfully manufactured from it, and preparations are afoot for the making of agar-agar, or katan, as some call it.

This is a pearly-white shiny product, invaluable to the medical profession, and an important food adjunct. It is used extensively throughout the world as a thickener in jellies and soups. It is also largely employed in the sizing of textiles, for stiffening the warp of silks, for clarifying beer, wines, and coffee, and in the making of moulds in plaster of Paris.

Our hospitals use it in large quantities as a culture medium for bacteria. In this respect it has no equal, being the only gelatine-like substance that can stand the necessary temperature. The medical profession declare that its chemical properties are such that it will displace many drugs, which leave a harmful after-effect. Up to the present the whole world has had to rely upon Japan for its agar-agar. We took over a hundred tons last year, paying for it at the rate of Is 3d per pound. There are over 600 factories turning out this product in Japan. The Japanese product is dealt with by hand, and the present price of labor is such that we could not compete with the low wages of the Orient. Now, however, special machinery has been devised which will enable us to manufacture the coveted article much cheaper than we can import it.

But iodine and agar-agar do not exhaust the list of articles that can be made from seaweed. For instance, from the kelps, the most abundant o? the seaweeds, an isinglass superior to the vegetable article can be made, as well as adhesive plasters, photographic films, potash, and algin.

Algin is a substance capable of a variety of applications in the arts and sciences. It possesses 14 times the viscosity of starch and 37 times that of gum arabic. As a sizing for fabrics it supplies the long-felt want of a soluble gum of great elasticity and flexibility.. From it. lozenges and jujubes can be made.

At the present time the Scottish factories are obtaining most of the raw material which they are converting into iodine from the west coast of Ireland. Here the peasants gather the seaweed, or kelp, and stack it on the beach, just out of reach of the tide, where they leave it until it becomes thoroughly dry.

It is then burnt, a wliolc stack at a time. This often means 15 to 18 hours' steady work for a dozen men. While in a semi-liquid state it is cut into blocks, and when quite cool is as hard and as heavy as iron. It is sold to the iodine manufacturers at from £3 to £5 per ton, according to quality.

In the case of agar-agar the seaweed is sent direct to the factory. It undergoes many processes, being subject in turn to great heat and cold. After some 72 hours of treatment the seaweed comes out as the white gelatine substance that is so much in demand.

We should understand that the most productive work in this day, both for time and eternity, is that of hearing Mass.