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The Intergovernmental Maritime Consultative Organization (IMCO) is in need of a simple, relevant flammability test method for the curtain and drapery fabrics used aboard ships. Two methods for measuring self-extinguishment of fabrics upon removal of the flame were compared. One was proposed by the United States' representative to IMCO, the other was an adaptation of a recently proposed method of the International Standards Organization (ISO). The effects of variations of the proposed test methods (changes in the ignition flame characteristics, bottom edge or surface ignition, and in the specimen suspension) were also investigated. In general, the relative ranking of the fabrics was not changed, though the individual afterflame time and char length results were affected by some of these variables. The advantages and disadvantages of the two proposed test methods are discussed and an improved method is recommended.

A work that because of the presence of an underlying painting, and probably also as a result of surface disturbances and overpaintings connected with this, is in only a moderately good state of preservation, but must nonetheless be regarded as an autograph work by Rembrandt, probably dating from 1631.

To enable a bricklayer to construct an arch over an opening in the wall of a building, the carpenter must provide him with a support on which he can lay his bricks to shape the arch. This support can be either a solid piece of timber cut to the shape of the bottom edge of the arch (figure 7.1) — which is called a turning piece — or a timber frame as shown in figure 7.2, which is called a center. The height of an arch and the thickness of the wall will dictate whether a turning piece or a center is to be provided. Usually, turning pieces are used only for fairly low segmental arches and for flat arches.

Two simple formulae are presented which predict stress concentration factors applicable to a two-dimensional symmetrical T-head configuration. This configuration consists of a deep head joined to a shank by fillet radii. The independent equations that predict stress concentration factors for the same geometry are derived for two different loading conditions. In one instance, a tensile force is applied to the shank end of the T-shape. Equilibrium of forces is attained by supporting the bottom edge of the head section, resulting in the shank section being pulled in tension. In the second instance, a compressive load is applied to the top edge of the head section while the configuration is again supported at the bottom edge. Thus, only the head section is stressed and in a compressive manner. Because the analysis is not exact, the magnitudes of the stress concentration factors resulting from the predictive equations appear to be overly conservative at some ranges of the geometry parameter ratios. Therefore, an arbitrary 'limit of application', as it is termed in the text, is recommended when using these equations. Again, because of the inexactness of the analysis, experimental stress concentration factors are indirectly obtained for the first loading condition and directly obtained for the second loading condition mentioned above. These data were obtained for several geometric ratios of the T-head configuration and compared to the corresponding predicted values.

The objectives of the studies presented in this paper were to investigate the effects caused by steel reinforcing bars on determining the depth of cracks which appear on the surface of a concrete structure. Numerical studies were performed to investigate the interaction of stress waves with reinforcing bars. A full scale reinforced concrete beam was constructed as an experimental specimen. The specimen was loaded until cracks occurred. To measure the depth of a crack penetrating into the specimens, two receivers were used and located on thee opposite sides of the crack. The first receiver on the impact side is used to obtain the time of impact initiation. The second receiver located on the other side of the crack is used to trace the arrival of the P-wave diffracted from the bottom edge of the crack. Subsequently, the depth of the crack can be determined. Experimental results show that if tests are performed on the regions without reinforcing bars, the crack depth can be obtained easily because the second receiver initially responds to the arrival of the diffracted P-wave. In the presence of reinforcing bars, the initial disturbance at the second receiver is caused by the arrival of P-wave propagating through reinforcing bars but its amplitude is much smaller than that associated with the following arrival of the P-wave diffracted from the bottom edge of the crack. It is concluded that the presence of reinforcing bars does not make it difficult to measure the crack depth.

The Rf value (ratio of spot migration distance to solvent front migration distance from the origin) is widely used to characterize component spots in TLC. A more valid parameter for multiple development techniques, however, is the distance of the spot from the bottom edge of the TLC plate. The exact conditions of chromatography must parameter in specific cases is presented.

Physical therapy for the neuromuscularly involved child frequently includes prone positioning as a part of developmental stimulation. Pillows, rolls, and wedges are usually used to achieve this position; however, when some children are placed prone, they immediately assume a total extension pattern with the arms hyperextended and internally rotated (Fig. 1). Preventing this pattern is difficult using the traditional devices. However, the high sides of spools on which rope or chain is commercially packaged are ideal for preventing this pattern and keeping the child's arms forward. The spools are made of metal, plastic, or heavy cardboard and come in a variety of sizes. They can be obtained, usually free, from stores that sell hardware, boating supplies, or mountain climbing equipment. To adapt a spool, cut a bottom edge from each disk to the level of the center roll.…

The following carpenter's contract of 14-73was found in the manuscript collection atElv~d~n Hall, Suffolk, and is published here by kind permission of the Earl ofIveagh. It is carefully-written on an'indented strip of paper measuri.ng 15,by 51inch~s, and is well preserve~ except for so~e damage at the bottom edge. It refers in considerable detail to the construction of an oak-framed farm building at Water, Hall in the parish of Wixoe, on the Suffolk side of the River Stour.· The building was to be a combined stable and shipp on (cattle-shed), 51 ft long and 19 ft wide. The two parties to the contract were Thomas Peyton the elder, lord of the manor of Water Hall, andJohn Whyghte, a carpenter of Sible HedinghaminEssex.1The total cost of the project was to be 100 shillings, paid in two instalments. Thomas Peyton's hall survives as a farmhouse, about !mile north-west fthe village of Wixoe (grid reference TL 709438). Unfortunately none of the surviving farm buildings is medieval, and the present farmhouse appears to be of seventeenth-century construction.2

To assess the moisture, use is made of the Assman psychrometer with the addition of a simple and easily made adaptation, which consists of a square polished metal box 4 in. × 4 in. × 2½ in., open at one end. Two holes, sufficiently large to hold the box against the air tubes by means of the threaded ends of the psychrometer cups, are punched in the closed end of the box, equidistant from the sides. In the middle of the bottom edge of each side a ½-in. square cut is made, and when the box is fitted over the psychrometer cups, the instrument is ready for use on livestock.

For detection of signals recorded in the form of minute pits along tracks as capacitance variations, a record stylus is disclosed as comprising a shank having a portion of cross-sectional area decreasing toward one end of the stylus. A diamond, partially embedded in the shank, has a decreasing cross-sectional area toward said end of the stylus as a continuation of the decreasing cross-section of the shank. The bottom and rear face of the diamond are inclined so that the adjacent angle therebetween is smaller than 90 degrees. An electrode attached to the rear face of the diamond extends from the bottom of the diamond toward the other end of the stylus. The electrode is thus inclined in a direction opposite to the direction of movement of the recording medium to provide less concentration of electric lines of force on the rear bottom edge thereof.

A microphone mount and plug mount for attaching to the side of a motorcyclist's helmet, said microphone mount adapted to secure a microphone boom positioning a microphone proximate the motorcyclist's mouth, the motorcycle mount characterized by a clamp portion adapted to forcefully engage the bottom edge of the helmet with minimum structure below the edge of the helmet, and a boom seat to receive the boom base and passage of electrical wires from the microphone mount. The plug mount defines a clamp portion similarly adapted to surround the lower edge of the helmet, and a plug seat defining a cavity adapted to receive a electrical plug and an opening to said plug seat cavity to receive electrical wires from said microphone mount and from a headset mounted interiorly to said helmet, the electrical plug receiving a mating electrical plug attached to wires connecting with audio accessories located on said motorcycle.

Escapes from conventional box traps, especially by previously captured animals, prompted development of an improved trap to catch woodchucks (Marmota monax). A comparison of trapping periods with improved and conventional traps showed a marked increase in the number of woodchucks captured with the improved trap, as well as an increase in the proportion of previously marked animals held. J. WILDL. MANAGE. 39(2):439-442 Although improvements in traps frequently are mentioned, data to support the contention rarely are presented. This paper describes some changes in design and presents data showing increased efficiency. A 1955-70 study of the woodchuck population on Letterkenny Army Depot, Chambersburg, Pennsylvania, required the use of live traps to capture the animals. Early in the project, woodchucks were trapped with box traps similar to those described by Mosby (1955) and Taber and Cowan (1969:284). The trap had a wooden treadle to which was fastened a heavy gauge wire supporting the door which fell from the inside when the treadle was depressed. It became evident that these traps were not efficient in holding woodchucks. The tendency of woodchucks to escape was greater for those with previous trap experience than for those captured for the first time. Woodchucks escaped by one of two means: (1) reaching in past the treadle for the bait while balancing the door on their backs, and then backing out, or (2) turning around and lifting the door with a front foot. A slight nick or hole in the bottom edge of the door provided a toehold for woodchucks to lift the door. If the bottom edge of the door fitted tightly, a few minutes of chewing provided the necessary hold. Trump and Hendrickson (1943) stated that woodchucks pushed on such a door but did not pull on it. MATERIALS AND METHODS The trap (Fig. 1) length was increased to 36 inches to prevent woodchucks from stealing the bait without being captured. A transom catch was used as a latch to sto animals from lifting the door from inside. Driving three nails through the top of the trap near the back end and addition of a metal lining to the inside of the door thwarted animals' attempts to chew out of traps. In addition, the triggering mechanism was improved and simplified by using a wooden post rather than wire. The post makes the trap easier to construct, easier to set, harder to trip accidentally, and easier to repair. The following materials were used: 2 pcs., 36 x 1 x 8-inch pine, top and bottom; 2 pcs., 36 x 1 x 10-inch pine, sides; 1 pc., 18 x 1 x 7-inch pine, treadle; 1 pc., 10 x 1 x 7-inch pine, door; 1 pc., 6 x 2 x 2-inch pine, treadle post; 1 pc., 8.5 x 7-inch aluminum "valley tin" or heavy sheet aluminum, door lining; 1, 10 x 9-inch piece of 1 x 2-inch welded wire, back end; 1, reversible transom catch; 4, 2-inch-#7 flat-head wood screws; 30, 0.75-inch wire staples; 21, 8d box nails; and 24, 0.75-inch 16 gauge nails. SStudy supported by National Institutes of Health (Grant HE12295). J. Wildl. Manage. 39(2):1975 439 This content downloaded from 157.55.39.17 on Fri, 02 Sep 2016 05:28:14 UTC All use subject to http://about.jstor.org/terms 440 AN IMPROVED WOODCHUCK TRAP Ludwig and Davis

A bulldozer having a transversely elongate cutter blade closely spaced from the bottom edge of the mold board is disclosed. The cutter blade is mounted for reciprocal motion in forward and aft directions relative to the mold board. Unidirectional force impulses are applied to the cutter blade in a forward direction to drive the blade intermittently forward without aft motion. Preferably, the unidirectional force impulses are applied by first and second matched force transmitting beams. Each beam has two divergent approximately straight legs that meet at a juncture to form an acute, approximately 90° angle, a node at the juncture, an input anti-node at the end of one leg, and an output anti-node at the end of the other leg at the input frequency. A source of vibrations at or near the resonant frequency is coupled to the input anti-node and the output anti-node is disposed in spaced aft relationship from the cutter blade within striking distance thereof. The beams are mounted adjacent to the rear surface of the mold board so the mold board extends into the space between the legs with the input anti-node disposed near the top of the mold board and the output anti-node disposed near the bottom of the mold board.

A mechanism for automatically blocking the gap between the bottom edge of a door leaf, hung to open and close within a surrounding frame, and the adjacent threshold, when the door is closed; and automatically unblocking that gap when the door starts to open again, comprises an elongate bar housed above a strip of material in the bottom edge region of the door leaf. The bar and strip of material each are coupled to respective attraction/repulsion elements. One element is a magnet and the other is a piece of material having a positive reaction to a magnet, typically a further magnet. One end of the bar or an auxiliary member coupled to the bar protrudes from an edge of the door adjacent the door frame. The arrangement is such that, with the door open, the strip of material is raised clear of the adjacent threshold. As the door closes, the protruding end of the bar or auxiliary member contacts the upright of the door frame and is moved longitudinally to take the two sets of magnets out of line with one another and to allow - or to positively repulse - the strip of material to fall and block the gap between the bottom edge of the door leaf and the adjacent threshold.

To the Editor: —In visiting hospitals in different parts of the country one is struck by the number of surgeons who fail to take reasonable precautions against hair and dandruff falling into the operative field. This has been noticed in pictures of operations. A common practice is to turn up the bottom edge of the cap in a neat fashion, leaving uncovered the occipital region, from which loose hair, dust, and dandruff may fall into the operative field when the surgeon leans over the table. Such wound contamination can result in infection. Wound infections of unexplained origin still occur, though the incidence is less than formerly probably because of the general use of antibiotics. In marked contrast to the careless attitude of these surgeons is that of nurses, whose hair is generally adequately covered, often with a hood. On the other hand, anesthetists not infrequently are offenders, either through thoughtlessness

To the Editor:— The interpretation of Master's two-step electrocardiogram tracings may be expedited by recording all four tracings on one strip of paper. The stylus of the electrocardiograph machine, is set to record as close as possible to the bottom edge of the paper and record the resting tracing. Opening the machine, the paper is manually wound back onto the feed roll. The stylus is then positioned above the first tracing, the patient performs the prescribed exercise, and the one-minute tracing is recorded. The same number of cycles or the same length of paper as the resting tracing are used for each lead. The paper is again wound backwards onto the feed roll and the three-minute tracing is recorded above the previous one, the rerolling is repeated, and the eightminute tracing is recorded above the previous (Figure). The first tracing can be positioned at the top of the paper, and