He was thus led to adopt that system of sowing his crops in rows or drills, so wide apart as to admit of tillage of the intervals, both by ploughing and hoeing, being continued until they had well-nigh arrived at maturity.
Manual labour in farming operations began to be superseded by the use of drills, hay-makers and horse-rakes, chaff-cutters and root-pulpers.
These are taken off and sown in drills, like seed.
The seed should be sown in shallow drills, 10 in.
The seeding follows immediately with four-horse press drills that cover 12 ft.
Compulsory attendance of young men at national guard drills is enforced for at least two months of the year, under penalty of enforced service in the Line.
This seems to be due to the dust abundantly produced in mining operations, and especially by machine drills when boring " dry " (rising) blast holes.
The increased mortality seems to be due to the general tendency toward forced speed in development work, which is secured by rapid drilling, and by an increase in the number of machine drills used in a single working-place.
Bituminous coal, natural gas and oil abound in the vicinity; the river provides excellent water-power; the borough is a manufacturing centre of considerable importance, its products including iron and steel bridges, boilers, steam drills, carriages, saws, files, axes, shovels, wire netting, stoves, glass-ware, scales, chemicals, pottery, cork, decorative tile, bricks and typewriters.
Another class of percussive coal-cutters of American origin is represented by the Harrison, Sullivan and Ingersoll-Sergeant machines, which are essentially large rock-drills without turning gear for the cutting tool, and mounted upon a pair of wheels placed so as to allow the tool to work on a forward slope.
Fire drills were universal.
Whatever the seeds, the ground should be made tolerably firm both beneath and above them; this may be done by treading in the case of most kitchen garden crops, which are also better sown in drills, this admitting the more readily of the ground being kept clear from weeds by hoeing.
For rock drills, and revolving saws for stone cutting, either diamond, bort or carbonado is employed, set in steel tubes, disks or bands.
It has been found that the " carbons " in drills can safely be subjected to a pressure of over 60 kilograms per square millimetre, and a speed of 25 metres per second.
There are no dated specimens till the Assyrian iron saws (48) of the 7th century B.C. Drills were of flint (49) for hard material and bead-making, of bronze for woodwork.
These tubular drills were used from the IVth Dynasty down to late times, in all materials from alabaster up to carnelian.
When maize is sown broadcast or closely planted in drills the ears may not develop at all, but the stalk is richer in sugar and sweeter; and this is the basis of growing " corn-fodder."
The principal articles of import are shirtings, drills, jeans and twills, opium, woollens, steel, lead, needles, J apanese sea-weed and sugar; and of export, wool, skins, beans and pease, straw braid, coal, dates, tobacco and rhubarb.
The city has various manufactures, including fire-arms, calendar clocks, traction engines, electrical appliances, patent chains, incubators, autophones, artesian well drills, salt, cement, window glass and wallpaper.
The conditions of enlistment and reserve in the territorial force are a four years' engagement (former yeomen and volunteers being however allowed to extend for one year at a time if they desire to do so), within each year a consecutive training in camp of 14-18 days and a number of "drills" (attendances at company and battalion parades) that varies with the branch and the year of service.
The harrows and drills are worked in "gangs" as the Seeding' ploughs were.