Stower concludes with these observations:

"It may not be improper, in this place, just to take notice of the great danger to the correctness of a work which arises from the practice, too common with some authors, of keeping their proof-sheets too long in their hands, before they are returned to the printer. As the pages in the metal get dry, the adhesion of the types to each other is weakened, and the swell or extension of the quoins and furniture, which the moisture had occasioned, is removed; so that there is great danger of letters falling out, when a form is long kept from the press. Nor is the danger which is hereby occasioned to correctness the only inconvenience; the impatience of authors to see their works in a fit state for publication is almost proverbial. The pleasure arising from beholding, as it were, the form and texture' of one's thoughts, is a sensation much easier felt than described. That authors, therefore, may partake of this pleasure in a speedy and regular succession, they should make a point of forwarding their proof-sheets to the printer as quick as possible, not only that they may the sooner be got ready for press, but that the work may proceed in a regular manner, without being interrupted by the forwarding of other works in lieu of that, the proof-sheets of which are detained beyond the proper time in the hands of the author.

"Authors are very apt to make alterations, and to correct and amend the style or arguments of their works when they first see them in print. This is certainly the worst time for this labour, as it is necessarily attended with an expense which in large works will imperceptibly swell to a serious sum; when, however, this method of alteration is adopted by an author, the reader must always be careful to read the whole sheet over once more with very great attention, before it is finally put to press.

"A proof-sheet having duly undergone this routine of purgation, may be supposed to be as free from errata as the nature of the thing will admit, and the word 'Press' may be written at the top of the first page of it. This is an important word to every reader: if he have suffered his attention to be drawn aside from the nature of his proper business, and errors should be discovered when it is too late to have them corrected, this word' Press' is as the signature of the death-warrant of his reputation; and if he is desirous of attaining excellence in his profession, will occasion an uneasiness of mind which will but ill qualify him for reading other proof-sheets with more care

CHAP. X.

BEING advanced thus far on our journey, and in our progress having touched upon most of the subjects connected with the composing department, we now beg leave, in closing the first portion of this volume, to present our readers, in the three following chapters, with a view of those materials which, though last in our arrangement, are still not the least in importance, namely, alphabets of the various known languages, and such other characters as are connected with every department of Literature and the Fine Arts. We are well aware that many will condemn their insertion as unnecessary; but, let us ask, are they not of the utmost importance to young compositors, who probably may not have seen any of them before? and when met with in old books, they are quite at a loss to know their meaning and signification: therefore, we trust that their utility will prove a sufficient apology for their appearance.

MATHEMATICAL, ALGEBRAICAL, AND GEO-
METRICAL CHARACTERS.

+plus, or more, is the sign of real existence of the quantity it stands before, and is called an affirmative or positive sign. It is also the mark of addition: thus, a + b, or 6 + 9, implies that a is to be added to b, or 6 added to 9.

minus, or less, before a single quantity, is the sign of negation or negative existence, shewing the quantity to which it is prefixed to be less than nothing. But between quantities it is the sign of substraction; thus, a-b, or 8-4, implies b subtracted from a, or 8 after 4 has been substracted.

equal. The sign of equality, though Des Cartes and some others use this mark ; thus, ab signifies that a is equal to b. Wolfius and some others use the mark for the identity of ratios.

X into, or with. The sign of multiplication, shewing that the quantities on each side the same are to be multiplied by one another, as a × b is to be read, a multiplied into b; 4 × 8, the product of 4 multiplied into 8. Wolfius and others make the sign of multiplication a dot between the two factors; thus, 7. 4 signifies the product of 7 and 4. In algebra the sign is commonly omitted, and the two quantities put together; thus, b d expresses the product of b and d. When one or both of the factors are compounded of several letters, they are distinguished by a line drawn over them; thus, the factum of a b c into d, is wrote dx a+b-c. Leibnitz, Wolfius, and others, distinguish the compound factors, by including them in a parenthesis thus (a+b-c) d.

by. The sign of division; thus, ab denotes the quantity a to be divided by b. Wolfius makes the sign of division two dots; thus, 12:4 denotes the quotient of 12 divided by 43. If either the divisor or dividend, or both, be composed of several letters; for example, a+bc, instead of writing the quotient like a fraction.

involution. The character of involution.

vy evolution. The character of evolution, or the extracting of roots.

7 or are signs of majority; thus, a 7 b, expresses that a is greater than b.

or

are signs of minority; when would denote that a is less than b.

is the character of similitude used by Wolfius, Leibnitz, and others: It is used in other authors for the difference between two quantities, while it is unknown which is the greater of the two.

:: so is. The mark of geometrical proportion disjunct, and is usually placed between two pair of equal ratios, as 3:6:4:8, shews that 3 is to 6 as 4 is to 8.

: or .. is an arithmetical equal proportion; as, 7.3:13.9; i. e. 7 is more than 3, as 13 is more than 9.

Quadrat, or regular quadrangle; as follows, AB=BC; i. e. the quadrangle upon the line AB is equal to the quadrangle upon the line BC. A Triangle; as, ▲ ABC=▲ ADC. Zan Angle; as, ▲ ABC=▲ ADC. Perpendicular; as, AB BC.

Rectangled Parallelogram; or the product

of two lines.

The character of parallelism.

Vequiangular, or similar.

equilateral.

right angle.

denotes a degree; thus 45° implies 45 degrees.

a minute; thus, 50', is 50 minutes:

denote seconds, thirds, and fourths: and the same characters are used where the progressions are by tens, as it is here by sixties.

the mark of geometrical proportion continued, implies the ratio to be still carried on without interruption, as 2, 4, 8, 16, 32, 64 are in the same uninterrupted proportion.