Original oil and gas trade magazine vintage ad for DRESSER INDUSTRIES of Houston, TX. BIG 90. Magcobar save safely when you shoot straight. Ten per cent of the cost of drilling a well is usually mud. The other ninety is made up of the other expenses. Magcobar sells mud and technology. Reduce drilling time, control fluid loss, control lost circulation, assure safety in high pressure zones. This unique 1962 multi-page technical oilfield petroleum drilling magazine advertisement would display beautifully matted and framed. Four page gatefold advertisement. Great graphics.