room and office, the point at which a dangerously high temperature or fire exists.
For the protection of city blocks, a system of hydrants and pipes placed on roofs has been suggested; water at an ample pressure to be constantly available. Very solid brick division-walls, carried up a few feet above the roof, are desirable in such blocks.
It may now be in order to state the progress of the mutual system of underwriting, whose methods have been briefly presented. On January 1, 1885, the nineteen associated Factory Mutual Insurance Companies had at risk no less a sum than $375,000,000, an amount nearly twice as large as that at risk seven years before. During these seven years the cost to the insurers in the leading company, the Boston Manufacturers', had declined twenty-three per cent, as compared with the cost during the years from 1850 to 1878. In the early part of this latter period the volume of business was small, and the losses proportionally greater than they afterward became. During 1884 the net premiums paid by insurers in the Mutual companies averaged 28·28 cents per $100 insured.
A few words as to the details of effecting the mutual insurance of factories: Although the cost is currently but 28 cents per $100 per annum, the companies charge rates averaging 80 cents, the difference being returned as dividend. In addition to the payment of premium, each insurer becomes liable for an assessment five times as great as the premium. No such assessment has ever been called for in the history of the Factory Mutual Companies. No policy is granted until compliance with the companies' rules for construction, quenching apparatus, and discipline in its use, has been ascertained by an inspector. His further business is to pay frequent and unannounced visits to insured premises, to see that all is as it should be. Disobedience to rules, or culpable negligence, may be deemed sufficient cause for canceling a policy. When an ordinary mill or factory adopts the means of safety laid down by the mutual underwriters, it is computed that the outlay is saved in premiums in two years.
In the foregoing paragraphs a form of scientific underwriting has been briefly described, which has important bearings on the general question of insurance and the reduction of the fire-tax. New England Mutual underwriters have ample scope for their activity in the pursuit of their business, and are very cautious in pointing any morals to stock-insurance companies. Mutual underwriting is well adapted to the kind of risks it accepts. These are large mills usually isolated. They fall into comparatively few classes, for which rules for construction and fire-appliances can be readily prescribed. Each passing year finds manufacturers more and more alive to the advantages of the mutual system, the last interest which has begun to adopt it being that of the rubber-factories.
Mutual underwriting can not be directly applied to the miscella-
