The rights of these parties are determined by the rules which apply between mortgagor and mortgagee. Many things which, as between landlord and tenant, would be remov-" able as chattels, are regarded as part of the realty, in favor of a mortgagee. In ascertaining what articles have become part of the realty, regard must be had to the manner in which, the purpose for which, and the effect with which, they are annexed. McLaughlin v. Nash, 14 Allen, 136. Pierce v. George, 108 Mass. 78. Whatever is placed in a building by the mortgagor to carry out the obvious purpose for which it was erected, or to permanently increase its value for occupation, becomes part of the realty, though not so fastened that it cannot be removed Without serious injury either to itself or to the building. On ;he other hand, articles which are put in merely as furniture are removable, though more or less substantially fastened to the building. So, too, machines not essential to the enjoyment and use of a building occupied as a manufactory, nor especially adapted to be used in it, are removable, though fastened to the building, when it is clear that the purpose of fastening them is *50to steady them for use, and not to make them a permanent part of or adjunct to the building. Winslow v. Merchants Ins. Co. 4 Met. 306. Hellawell v. Eastwood, 6 Exch. 295. The Queen v. Lee, L. R. 1 Q. B. 241. Pierce v. George, above cited.
The engine and boiler, which were put in to supply the premises with power; the steam-gouge, which is essential to the safe use of the same; the water-tank, for supplying the building with water for general use; the steam-pump connected therewith, and the shafting, are evidently designed as permanent additions to the realty, and could not be removed without seriously injuring the value of the building for use.
The other articles named in the agreed facts are in no way essential to the enjoyment of the estate; they are incidental merely to the particular business carried on at the time; and, though some of them are affixed to the building by nails or bolts, it is clear that the object of affixing them is only to secure them so that they may be advantageously used, and not to make them permanent parts of the building. They are therefore chattels; and for their value, to be ascertained by an assessor, there must be .Judgment for the plaintiff.