B, anterior portion more highly magnified (from Marshall and Hurst, after Sommer); cs, cirrus sac; d, ductus ejaculatorius; f, female aperture; o, ovary; od, oviduct; p, penis; s, shell-gland; t, anterior testis; u, uterus; va, vp, vasa deferentia; us, vesicula seminalis; y, yolk-gland; **yd**, its duct.

**Yd**., are removed monthly, their gold content being from 0.5 to 1 0%, and after folding are melted in reverberatory furnaces to ingots containing 2 to 4% of gold.

The rails used are of flat bottomed or bridge section varying in weight from 15 to 25 lb to the **yd**.; they are laid upon cross sleepers in a temporary manner, so that they can be easily shifted along the working faces, but are carefully secured along main roads intended to carry traffic continuously for some time.

- 1 or, as (88) and (90) may be written for small angles, (91) sin 20.=2C [I (V) - oS j, (92) sin 20 =2C [O S - I (v)] To simplify the work, so as to look out the value of sin 20 without the intermediate calculation of the remaining velocity v, a doubleentry table has been devised by Captain Braccialini Scipione =S (U) - S (u), = I (U) - I (u); mean angle (70), (Problemi del Tiro, Roma, 1883), and adapted to **yd**., ft., in.

By 24 **yd**., and a usual count is 18X18.

Of Ostend was the Tirpitz battery with 4 r r-in: ranging 35, 000 **yd**., and 3 m.

Guns at 1,000 **yd**., and the chance of success depended largely on an effective smoke screen.