248 ANNUAL REPORT 
CHAPTER VIL. 
WINNING AND PREPARATION OF THE RAW MATERIALS. 
According to the nature of the various raw materials the method 
of winning them must differ. It is impossible to consider all the details 
of the quarrying and digging, but we must let it suffice to make a brief 
outline of the processes practicable. 
THE CLAYS. 
As to the clays, we have, according to their nature, the following 
methods of winning them: 
tr. Hand digging. 
2. Quarrying. 
3. Use of plow and scraper. 
4. Steam shovel. 
Go IDyreckoivare, 
6. Mining. 
Hand Digging.—Hand digging is practiced where the daily output 
is small and the clay is soft enough to be picked and shoveled without 
too much effort. The cost of digging clay is at least 35 cents per cubic 
yard. 
Quarrying.—Quarrying is employed with shales. The material is 
worked in benches and is blasted with powder, dynamite being as a rule 
too quick in its action. By means of proper “undercutting” large quan- 
tities of material can be handled. The cost is probably around 25 cents 
per cubic yard. 
Plow and Scraper. —The plow and scraper are very suitable in 
larger areas of soft clay, comparatively level. The common scrapers 
should not be used for distances over 200 feet. For greater distances a 
platform may be used, to the top. of which the scraper is drawn and 
dumped through a grating into a car, cart or wagon. The wheel scraper 
may be used for longer distances, not exceeding 500 feet. The cost per 
cubic yard is about 20 cents. 
Steam Shovel.—The steam shovel, either continuous with an endless 
chain carrying buckets with a cutting edge or intermittent like the usual 
