Inch

“ A body has six sides, each side measuring an inch in length, what is its diameter across corners? Find a horizontal line that measures an inch from its intersection of the line o b to the line of 45 degrees, and along this latter to the point o is one-half the diameter across corners. ”

“ Thus, a line one inch long may be conceived as made up of pieces, each of an inch long; or of parts, each part being of an inch long; or of parts, each of which is of an inch long; or, pushing the thought to the limits of conceivability, it may be regarded as made up of an infinite number of elements each of which is infinitesimally small. ”

“ Several hundreds in number, and not far from a quart in quantity, are in our possession, which retain their structure sufficiently well to be strung and handled. The largest of these measures two and a half inches in circumference, or upwards of three fourths of an inch in diameter. They are of all intermediate sizes, down to one fourth of an inch in diameter. Most are irregular in form, or pear-shaped; yet there are many perfectly round. They have been obtained from separate localities, several miles apart, and from five distinct groups of mounds. ”

“ Objectives of an inch and half inch, and, for some starches, one-fifth inch, equivalent focus, are sufficient. One eye-piece of medium depth, one-fourth to one-sixth, adjusted at 160 degrees is enough, with plenty of good light. ”

“ A linear inch measured on the sides or belly, longitudinally, contains twelve scales, the scales on the belly having, however, less vertical breadth. On the back an inch includes seventeen or eighteen. The asperity of the scales is perceptible to the finger, when it is drawn over them from the tail toward the head. ”

“ A half inch, inch, or inch and a half hole is bored with an auger, but if we should wish, in the same manner, to bore a hole a quarter of a foot in breadth, it is impracticable, while one of half a foot or more seems not even conceivable. ”

“ If the sun, for example, have from six to twelve inches diameter, the width of the strokes that form the spiral need not be more than one-twentieth part of an inch, and the spaces between them that form the transparent parts, about two-tenths of an inch. ”

“ To begin draw a line from A to B and B to D. Measure from A to B, 3 inches, and from B to D, 15 inches, which is 14 inches for all-around neck measurement and 1 inch for seams. Then measure from D to C, 3 inches, and connect a line from A to C. Now divide from B to D, making E, and draw a line up from E to F. Raise up from B to H and D to I, 1 inch each and lower from F to G, with 1 inch at the center line. ”

“ An object one hundredth of an inch in diameter, or of which it would take one hundred placed side by side to make an inch, is about the smallest thing that can be easily seen by the unassisted eye. Take a piece of card and punch a little hole through it with the point of a small needle, hold it towards a lamp or a window, and you will see the light through it. ”

“ For instance, if a 67-inch roll, 7,000 yards long, weighs 1,200 pounds exclusive of core, and measures 32 inches in diameter, these figures when worked out into reams show that that paper averages .30.7 pounds to the 500 sheets, measuring 24 by 36 inches, and that the paper has been well calendered. ”

“ I need not say that we may make scales in any proportion ad infinitum—one, two, or three hundredths of an inch to a foot, or to 10, 100, or 1,000 feet, as we do for drawing maps. In the same way we may give details on a scale of 6 inches to a foot, or half the actual size; 2 inches to a foot, or a sixth of the actual size, &c. Having chosen his scale, the architect is enabled to give to each part of the plan exact relative dimensions. If he has adopted the scale of one-eighth of an inch to a foot, and wishes to indicate a door 4 feet in width, he takes 4/8ths. ”

“ In small cylindrical bodies, as, say 1/4 inch in diameter, the darkest line of shadow may be located at the lines representing the diameter of the piece, but [294] in pieces of larger diameter the darkest line may be located at a short distance from the line that denotes the diameter or perimeter on the shadow or right-hand side of the piece, as is shown in many of the engravings that follow. It is obvious that if a drawing is to have dimensions marked on it, the coloring or tinting should not be deep enough to make it difficult to see the dimension figures. ”

“ This comparison is called a ratio. For instance, the ratio of the foot to the inch is 12, and is found by dividing the foot by the number of inches in a foot. What is the ratio of the yard to the foot? ”

“ If it were possible for man to construct a globe 800 feet, or twice the height of St. Paul’s Cathedral, in diameter, and to place upon any one point of its surface an atom 1/4380th of an inch in diameter, and 1/720th part of an inch in height, it would correctly denote the proportion man bears to the earth upon which he stands. ”

“ The upper horizontal Figures shew the Number of Parts into which the Tenth of an Inch has been divided.
2. The Figures in the left vertical Column express the Height in feet, (above the imaginary Level, at 32 Inches of the Barometer,) or Expansion corresponding to a single Tenth of an Inch of Quicksilver.
3. The feet in the Place of Meeting are called tenths: thus, 90 Feet are 9 Tenths of 100 Feet. ”

“ To measure 1⁄2 inch, for illustration, five complete revolutions of index-wheel should produce 1⁄2 inch, and would if we had a perfect screw, but the screw is not perfect, and we must add to the measurement already obtained one-half of the space, stamped upon corrective devise, 0-1. ”

“ For machine and shop work the English unit is the inch and fractions, and countries having the metrical standard have universally adopted the millimètre.
The inch is well fixed in the minds of all mechanics by constant use, and the ease with which the fractions are had by halving only renders the system very convenient. ”

“ I was told that the surface of the body, or the skin of a large man, measured sixteen feet square, which is equal to the surface of a table four feet long and four broad. Now, you know that in four feet there are forty-eight inches, and on the surface of the table are forty-eight rows, with forty-eight inches in each, or 2,304 square inches; so that a man's surface is 2,304 square inches, and the weight his body supports is 34,560 lbs., or upwards of fifteen tons—always at the rate of fifteen pounds to every square inch, you understand. ”

“ An ant measuring say one-sixth of an inch, the pencil, being seven inches high, is consequently forty-two times as long as the ant. It bears, therefore, somewhat the same relation to the ant as a column two hundred and fifty feet high does to a man. The pencil having been moved six inches, it is as if a man in a country he knew well would be puzzled at being moved a few hundred feet, or, if put down in a square containing less than an acre, could not find a column two hundred and fifty feet high, that is to say, higher than the Duke of York's column. ”

“ When, however, you learn that most of them are only about twenty-five thousandths of an inch long and that a thousand million of them could be packed comfortably into a little box, whose sides measured but a twenty-fifth of an inch in length, it is not really so surprising after all. ”

“ When the dimensions, in fractions of an inch or in millimetres, and the weight, in fractions of a pound or in grammes, are given, the expert foreman or workman, confidently and without reflection, infers the rest of what need be known of the uses to which any given item that passes under his hand may be turned. ”

“ In every drop of dirty, stagnant water, we are generally, if not always, able to perceive, by means of the microscope, moving bodies, of from one eleven hundred and fiftieth to one twenty-five thousandth of an inch in diameter, and which often lie packed so closely together that the space between each individual scarcely equals that of their diameter.”—Prichard, History of Infusoria, p. ”

“ A hair two and a half inches long, which is perhaps near the average length, will stretch about one fourth of an inch before breaking. The diameter decreases rapidly both at the top and bottom, but is maintained throughout the greater portion of the length with a fair degree of regularity. ”

“ In the centre of an adult's back the lumps are about three inches long, by a thickness in the middle of about three-quarters of an inch, and the short ones on the shoulder are two inches in length, with a diameter in the middle of half an inch. ”

“ With a four-foot rule, I was but little advanced towards my computation. I might make a nearer approach to the measurement of my diameters, but that would not avail. I must know them exactly. I must know them in inches, and even fractions of inches; for, as I have said, an error of half an inch in some of my data would make a difference of gallons in the result. How, then, was I to divide a four-foot stick into inches, and register the inches upon its edge? How was this to be done?
It seems simple enough. The half of my four feet—already ascertained—would give me two feet ”

“ A very good way to discipline the mechanical eye is to first measure an inch with the eye, and then prove it with the rule, then measure a half inch, then an eighth, and so on, and you will soon be able to discover at a glance the difference between a twelfth and a sixteenth of an inch ”

“ An interesting fact to be noted is, that the fourth finger and from the point where the bones of each finger unite with those of the hand. A centimetre is practically equivalent to two fifths of an inch. ”

“ For an iron ball, whose diameter is given, supposing a 9-pounder, which is nearly 4 inches, say, the cube root of 2.08 of 9 pounds is, to 4 inches, as the cube root of the given weight is to the diameter sought. Or, if 4 be divided by 2.08, the cube root of 9, the quotient 1.923 will be the diameter of a 1-pound shot; which being continually multiplied by the cube root of the given weight, gives the diameter required. ”

“ No. VI. contains the number of French cubical inches and decimals contained in the corresponding ounce-measures used in the experiments of our celebrated countryman Dr Priestley. This Table, which forms No. III. of the English Appendix, is retained, with the addition of a column, in which the corresponding English cubical inches and decimals are expressed. [Pg xi]
No. VII. Is a Table of the weights of a cubical foot and inch, French measure, of the different gasses expressed in French ounces, gros, grains, and decimals. ”

“ They are circular in form and have a smooth exterior, and are on an average 1/3200 part of an inch in diameter, and are about one-fourth of that in thickness. Hence more than ten millions of them may lie on a space an inch square. ”

“ If the head is to receive stars, it must not be above 8 inches high. To construct the wings, take a thin piece of deal, or tin, and cut out a right-angled triangle, fig. 157. Make a b = 71⁄2 inches, b c = 11⁄2 inch. ”

“ This cutting-in is but one Inch broad at the farther side the Cheek, and an Inch and a quarter on the hither-side the Cheek. The under-side of this Cutting-in, is straight through the Cheek, viz. Square to the sides of the Cheek: But the upper-side of this Cutting-in, is not square through the Cheeks, But (as aforesaid) is one quarter of an Inch higher on the fore-side the Cheek than it is on the further side; So that a Wedge of an Inch at one end, and an Inch and a quarter at the other end may fill this Cutting-in. ”

“ A large notch of an inch and a half in width signified 1000l.; a smaller notch, one inch in width, signified 100l.; one of half-an-inch signified 20l.; a notch in the wood slanting to the right signified 10l. (in combination this notch was placed before the 20l. notch) ; small notches signified 1l. each; a cut sloping to the right signified 10s. (in combination placed before the 1l. marks) ; slight indentations, or jags, in the wood signified shillings; strokes with ink on tally signified pence; a round hole, or dot, signified a halfpenny ”

“ If a man of 5 feet 7 inches give 101⁄2 inches for head and neck, 25 for trunk, and 311⁄2 for fork, what should another give, of 6 feet, or any other height? The approximation of a man's actual measurement to this rule of three determines his pretensions in the way of symmetry; and the inventor of the shibboleth has found it so far to answer, that a figure coming near the rule invariably pleases the eye, and gives the assurance of a handsome man. ”

“ He says that from experiment he finds it will usually require about 108 to 120 lines within an inch to give to the naked eye the idea of a flat tint or wash, but that about 80 to an inch is as many as can be drawn to the inch by unaided vision; eighty lines to the inch gives 120 in 11⁄2 inches, which, if reduced in reproduction by one-third, will give the requisite number of 120 to the inch which Mr. ”

“ A man of correct proportions will, in general, be about the same height as the length of the arms from tip to tip of the long fingers, when extended. I have frequently seen cases of factory deformities, in which the length of the arms thus, was six inches more than the altitude of the body; in my own case, this difference is eight inches. I have observed, that, so far from the ratio of these cripples being in proportion to the weight of the work to be done, it is directly the contrary ”

“ Unless working to some uniform scale, an object should be shown as large as the plate allows; always remembering that a lantern slide will seldom take more than 3 inches diameter, and hardly a full 3 inches square. ”

“ In like manner, of fifty young persons of the average of fourteen years and eleven months, the measurement in height was four feet five inches, and in circumference two feet three inches; while of forty-nine young persons employed on farms, of the average of fifteen years and six months, the measurement in height was four feet ten inches and eight-elevenths, and, in circumference, two feet three inches, being a difference of nearly six inches in height in favour of the agricultural labourers. ”