304 IOWA DEiPARTMENT OF AGRICULTURE 



many drove to Des Moines from far corners of the state, and brought 

 their camping outfits along. No charge is made for camping privileges, 

 but the fair management goes to considerable trouble and expense to 

 provide conveniences for those who prefer to spend their entire time 

 on the grounds. Campers had access to well-organized grocery stores, 

 moved to the fair grounds for the occasion, and for nearly two weeks 

 the proprietors did a thriving business in supplying the needs of the 

 tented city. Many who came in automobiles brought along their camp- 

 ing equipment in two-wheeled trucks attached to the rear of their cars. 

 These attachments are being found very useful for carrying light loads 

 to and from the farm, or in carting baggage on a longer tour, such as 

 to the state fair. 



Practically every type of country road and city street could be in- 

 spected at the headquarters of the Iowa State Highway Association. 

 There was a plain dirt road, an oiled dirt road, a gravel and an oiled 

 gravel road, asphaltic macadam, one and two-course concrete, fiber 

 brick, asphaltic concrete, sheep asphalt pavement, creosote wood 

 blocks, and brick. Photcs on the walls illustrated the methods of road 

 building, grading, oiling, construction of culverts, and other phases of 

 work looked after by the highway commission. The disastrous effects 

 of bridges which had been found wanting when they had to support a 

 heavy load, also could be seen. The exhibit was of particular educa- 

 tional value to those responsible for road building, and to every farmer 

 and taxpayer of the state. Members of the commission took turns in 

 explaining the display on different days of the fair, and the tent had 

 its share of attendance daily. 



An educational plea for the more extensive use of Iowa coal was 

 made at the headquarters of the mine and mining department. The 

 usual guessing contest, in which all were invited to estimate the 

 weight of a pyramid of coal in front of the building, was repeated. 

 Statistics displayed showed that coal is mined in twenty-three Iowa 

 counties, and that the industry gives employment to 17,000 men yearly. 

 Approximately 8,000,000 tons of coal are mined in Iowa each year, and 

 its total value amounts to $25,000,000. Tests made by the Agricul- 

 tural College indicate that Iowa coal is superior to much eastern coal, 

 for which considerably higher prices are charged, the retail cost of the 

 former being about $4 a ton, as compared with $5.50 to $7.25 for the 

 latter. 



In the same building with the mining products was a display ar- 

 ranged by the Geological Society. This was of interest to a great many, 

 especially the exhibit which showed the different steps that clay and 

 lime go through in the manufacture of Portland cement. First there 

 was the rough limestone, then the clay, and the ground mixture of the 

 two materials. When the mixture is burned to fusion in kilns, clinkers 

 are formed, and to these gypsum is added and ground up. The gypsum 

 helps to govern the setting properties of cement. The next process 

 with the ground mixture of clay, limestone and gypsum brings about 

 the finished product of good Portland cement, of which thousands of 

 barrels are used in Iowa yearly. Brick and tile were included in the 

 society's display. 



