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1) THREE CITIES WHICH FORM THE VERTICES OF A TRIANGLE
QUESTION:
The Gemara says that when three cities lie at the vertices of a triangle, the middle city is able to "link" the two outer cities, allowing a person to walk from one to the other even if the distance between them is more than 4000 Amos. The Gemara adds that this rule applies only if two conditions are met. First, there may not be more than 2000 Amos between the middle city and each of the outer cities. Second, the middle city must be large enough so that if positioned on a line connecting the two outer cities, the edges of the middle city would lie within 141 1/3 Amos (two Karpifos) of each of the outer cities. In such a case, we view the three cities as if they were one large city and allow a person to walk from one outer city to the other even if they are separated by a distance of more than 4000 Amos.
The Gemara asks how this case differs from the case of a city in the shape of a bow. In that case, the two ends of the city must be within 4000 Amos of each other in order to permit one to walk from one end to the other. Why do we not say in that case as well that the houses in the "bow" part of the city may be viewed as situated between the two tips, and thus those houses join the ends to permit one to walk even farther than 4000 Amos to get from one city to the other? Why do we not look at the space between the tips as filled up with houses?
The Gemara answers that we cannot view the empty space between the two tips of the bow-shaped city as filled up with houses ("Mali").
Why not? The Gemara does not explain the difference, nor does Rashi seem to shed any light as to why the part of the city in the "bow" cannot be used to fill up the space between the two ends of the bow!