These rods, or rules, are used to ascertain the capacity of a barrel ; the want age rod is used in connection with the gauging rod. The No. 44 has 12 tables, for barrels of 16 to 120 gallons capacity. Stephens' Combination Rule. This combinesSLIDE RULES.* (Fig. 142).
These Rules are very largely used by the most intelligent class of engineers, architects, scientists, designers of machinery, surveyors, and intelligent mechanics generally. They are also particularly adapted to the use of persons having charge of Cotton or Woolen machinery. The quickness and ease with which different calculations can be made, is little short of marvelous.
We have an improved treatise on the Gunter's Slide and Engineers' Rules, showing their utility, and containing full and complete instructions; 200 pages, bound in cloth.
Faber's improved Calculating Scale (Fig. 143). Price, with book of instructions, $3.60. This Calculating Scale, or Mathematical Rule, is made of boxwood, is 101 inches long, and has a traversing slide of nickeled metal.
Keuffel & Esser's Slide Rule. Price, with directions, $4.50. Is similar to the above, but is divided on celluloid facings. Can furnish this in 20 inch size ; price, $16.50. The 20 inch size has an advantage, in that they admit of finer divisions and consequent closer readings. Thacher's Calculating Instrument, performs the greatest variety of useful calculations, with unexampled rapidity and accuracy. Cylinder, 18 inches long, in polished mahogany box. Same as No. 1740, but with 3 inch Reading Glass sliding on brass bar, and adjustable.
FLEXIBLE FOLDING RULE. These pocket rules are,to a great extent, taking the place of the ordinary two foot rule. They are made from two to six feet long, machine-divided and accurate. As they are made of very thin wood, the divisions can be brought close to the object measured. They have spring joints, which hold rule in a straight line when open. Perhaps their greatest advantage, how-ever, is in their extreme lightness, the two foot rule weighing but one ounce.
HICKORY, BOARD AND LOG RULES.
THREE TIER BOARD RUMM.
FIVE TIER BOARD RULE.
These are made of the best second growth hickory, hand shaved. Figures are burned on the wood.
The log rules are furnished regularly with the Doyle or Scribner, scale of measurements, but we can furnish any other scale that may be wanted.
Can furnish Log rules for any diameter or length measurements desired. -
For all special rules an extra price will be charged.
STEEL BOARD RULE.
No. 51, $2.80. 3 Tier, 31 ft., Inspector's. The Steel Board rule, Fig. 151, has been 'in use for some time, and is giving excellent satisfaction. It is nearly as light 'as a wooden rule, weighing less than six-teen ounces. Is nickel plated and lacquered to prevent rusting.
LUMBER GAUGE. A neat device, worn on the finger, for determining the thickness of lumber. Can be carried in vest pocket.
IMPROVED MARKING STICK. in itself a Rule, Spirit Level, Plumb, Square, Bevel, Indicator, Brace Scale, 'Draughting Scale of equal parts, T Square, Protractor and Right Angle Triangle.
This is adapted to lumber crayons of Board and standard makes ; is 36 inches long, with
Log rule combined ; Brazed Head. hickory handle.