Page. Col. 607 2 last two lines, for $-b^3$, read $+b^3$. 610 2 line 4, for $a+x^3$, read $a^2+x^3$. 611 2 — 30, for $\frac{1}{a^4} = \frac{a^2}{a^4}$, read $\frac{1}{a^2} = \frac{a^2}{a^4}$. 612 1 — 1, for $x^{-3} \times x^{-3} = x^{-3}$, read $x^{-3} \times x^{-3} = x^{-3}$. — 2 — 37, for $a^n +$, read $a^n -$. — — — 40, for $a-x$, read $a+x$. 613 1 — 9, for $\frac{x^2}{2} = 6d^2z$, read $\frac{x^2}{3} = 4d^2z$. — — — 13, for $6d^2z$, read $4d^2z$. 616 2 — 13, for $\frac{3}{2} \sqrt{2}$, read $\frac{3}{2} \sqrt{2}$. — — — 14, for $\frac{3}{2} \sqrt{\frac{3}{2}}$, read $\frac{3}{2} \sqrt{\frac{3}{2}}$; also for $\frac{3}{2} \sqrt{2}$, read $\frac{3}{2} \sqrt{2}$. 624 2 — 10, also line 12, for $(3x+a)$, read $(3x-a)$. 627 2 — 37, for $abc-ac$, read $ab-ac$. 628 2 — 42, for $x=7$, read $x=-7$. 629 2 — 54, for $v+x=p$, read $v+x=p$. 630 1 — 3, for § 148, read § 147; line 18, for § 154, read § 153; and line 19, for § 153, read § 152. 631 — 5, for $-20$, read $-20x$. — 2 — 22, for $x^2$, read $x^2$. 632 1 — 31, for $qx+r$, read $qx+r+x+s$. 634 1 — 38, for the first, read, the second. 637 1 — 27, for $x-y+1$, read $x+y+1$. 638 1 — 9, for $+ga$, read $-ga$; and line 37, for $b$, read $b$. — 2 — 25, 28, and 29, for col. $a$, read $\frac{1}{4}$ col. $a$. 639 1 — 2 and 5, for col. $a$, read $\frac{1}{4}$ col. $a$. — — — 9, for col. $a=\frac{r}{n^3}$, read col. $a=\frac{3r}{n^3}$. 640 1 — 28, 29, 30, for $\sqrt{Ry}$, read $\sqrt{Ry}$. 642 2 — 2, for $\frac{1}{x^2}$, read $\frac{1}{x^2}$. 648 2 — 14, for $\frac{1}{y}$, read $\frac{1}{y}$ twice. 651 1 — 24, for $(1+y)^m$, read $(1+y)^m$. 660 2 — 2, for $b$ read $c$. 665 2 — 4, $8q^2+p^2$, read $8q^2-p^2$. 667 1 last line but four, for $AC=a$, read $AC=b$. 669 2 line 8, read, if $AK$ be taken $=a+c$, the ordinate $K_4$. 674 — 7, for col.$a+\ldots$, read $c=col.a^2+\ldots$ — 2 last line but five, for $y^2$, read $y^3$.