in clothes " | — | — | 42 | — | — | — | — Time required to generate 221 deg. | | | | | | | in clothes " | — | — | — | 127 | 92 | 81 | 107 Total duration of process " | 135 | 105 | 57 | 127 | 101 | 87 | 107 Water evaporated, in gallons | 6.93| — | — | 9.24| — | 3.63| 4.84 Consumption of spirits of wine pints | — | — | — | — | — | — | — Consumption of gas, in cubic feet | — | — | — | — | — | — | — Consumption of cokes, in cbs | — | — | 8.8 |16.5 | — | — | — Consumption of charcoal, in cbs | — | — | — | — | — |14.3 |13.8 ----------------------------------------+-----+-----+-----+-
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N.B.—­In every case, even in the trials V. and X., in which the temperature in the disinfecting chamber rose above 320 deg.  Fah., the clothes, owing to the complete saturation of the hot air with live steam, remained absolutely unimpaired.

The column “water evaporated” shows the quantity of live steam passing through the disinfecting chamber averages 13 cubic feet per minute with gas or spirits, and 22 cubic feet with charcoal or coke in the portable and 33 cubic feet in the stationary apparatus.  Trials VI., VII., and VIII. took place in open air.

According to trial XII., from 28 to 30 complete suits of clothes can be disinfected at an expenditure of about 75 cbs. of coke per diem.

* * * * *

DRAWING INSTRUMENT FOR ACCURATE WORK.

BY J. LEHRKE.

This arrangement consists in a cylindrical metal or horn mounted lens two to four centimeters long, and magnifying two or three times, and two or three centimeters in diameter, whose side is provided with a contrivance for holding after it has been pushed into place a copying needle, a protractor, etc.

While hitherto the architect in using millimeter paper must hold separately in his hands a magnifying glass and needle, while the engraver holds the engraving tool inclined in one hand and the magnifying glass in the other, or must work under a large lens standing on three feet, it is now possible by a firm connection between the lens and needle or other instrument to draw directly with one hand and under the lens.  In the accompanying cut one of these lenses is shown in section, A, in which the glass is set obliquely, in whose focus the needle, a, is held and the field of view is enlarged.  A longer description is unnecessary, as the illustration gives the best explanation.  It need only be remarked that the stud, s, projecting a little near the glass, is for the purpose of preventing the instrument from leaving the position coinciding with the plane of the drawing.  For architects and engineers is provided a small compass, b, of about 2 cm. diameter,