Page 3 Advertisements Column 1

Greymouth Evening Star, 18 March 1947, Page 3

How wet is ‘damp’? tw HMHMMMMBI aw i 111 iii IS Wf ' H IHI ■ liwt'MM M■« 1 QBMWw Mil Rmhl! !i'. MHp iSMwi SwH®-' ti jO' wfc ißgpW' p B'| jw| Illi I : JU ■ _ . I-i How damp is your cellar? The chemise can. tell you by using an instrument called a Psychrometer which is illustrated here. This piece of equipment is used for measuring "relative humidity,” that is, the amount of moisture actually in the air compared with the greatest amount that could be present at the same temperature. This psychrometer depends for its action on the fact that when strong sulphuric acid combines with water a considerable amount of heat is liberated. A measured quantity of the air under, examination is passed over the bulbs of two thermometers which are graduated to one-hundredth of a degree. Strong sulphuric acid drips on to the second thermometer, and combines with any moisture which may be present. The heat produced, which is proportionate to the amount of moisture absorbed, is registered on the scale of the thermometer. By comparing the temperatures registered by the two thermometers, the relative humidity can be calculated very accurately. The psychrometer is used to discover whether any moisture is present in industrial gases when complete dryness is important. It is so accurate that it will detect as little as one part of water in a million of gas. This information is essential in such operations as the bright heat treatment of Jrg -H metals, when compounds containing oxygen—of which ff Ijj 1| water is one—must be excluded to avoid tarnish. This psychrometer is one of the most sensitive instruments used by the British chemical industry in its service to the community. Nos 12 in the "Equipment of an Industry” series inserted by IMPERIAL CHEMICAL INDUSTRIES (N.Z.) LTD.

S* * fl, fc &OJE (foorpclown W **"“sn the > Q Highways Man y accidents to cyclists are caused by thoughtlessness, X. by “showing off”, '" \\ or ignoring traffic rules, JNUX V| ! f D© ) ; jS Reep t 0 t b £ ieft and nde without wobbling across ! the road. @ Give way to traffic [ on the right and, if turning to the right yourself, - give way to all traffic. ® Keep your speed F down. ® Obey traffic lights and give correct ? hand signals. © Ride carefully and don’t “show off”. : V ISSUED BY THE TRANSPORT DEPARTMENT NEW ZEALAND RAILWAYS AIR LINK Daily Inter-Island Cargo Service | New Zealand Railways’ air cargo service, operating daily (except , Sundays) between Wellington and Blenheim, provides facilities for through booking of goods and parcels from any railway station in the North Island to any railway station in the South Island, and vice versa. Speedy inter-island transit connecting with express goods service in both islands. Reasonable rates, Ask Your Nearest Stationmaster For Particulars # K’ ’’orkmgBoots d «» C2? xj Hard roads and muddy fields test the solidity of Boots. Our Working jsj Boots stand every test and give the vj long wear you expect. Strongly made XI with solid leathers, soles reinforced <M with Heelplates, Toeplates and Hob- Y' »aiU gricea are low. REYNOLDS SHOE SERVICE | 30 Tainui Street. ’Phone 1092. 3<